what is helium? helium is a chemical with the symbol he and atomic number 2. it is colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table

Answers

Answer 1

Answer: They are all true

Explanation:

Helium is a noble gas and non oder and such


Related Questions

which will form hydrogen bonds between its molecules? a) ch3ch2ch2f b) ch3ch2ch2ch3 c) (ch3)3n d) ch3ch2och3 e) ch3nhch2ch

Answers

Option A and D, CH3CH2CH2F and CH3CH2OCH3 will form hydrogen bonds between its molecules. Hydrogen bonding occurs between the polar molecules.

A) CH3CH2CH2F will form hydrogen bonds between its molecules due to the presence of a hydrogen atom and a strongly electronegative fluorine atom. The hydrogen atom will form a polar covalent bond with the fluorine atom, which creates a dipole moment and results in hydrogen bonding between molecules.
B) CH3CH2CH2CH3 will not form hydrogen bonds between its molecules due to the lack of an electronegative atom that can interact with the hydrogen atom to form a polar covalent bond.
C) (CH3)3N will not form hydrogen bonds between its molecules due to the lack of a hydrogen atom to interact with the nitrogen atom.
D) CH3CH2OCH3 will form hydrogen bonds between its molecules due to the presence of a hydrogen atom and a strongly electronegative oxygen atom. The hydrogen atom will form a polar covalent bond with the oxygen atom, which creates a dipole moment and results in hydrogen bonding between molecules.
E) CH3NHCH2CH will not form hydrogen bonds between its molecules due to the lack of an electronegative atom that can interact with the hydrogen atom to form a polar covalent bond.

For more such questions on Hydrogen bonding , Visit:

https://brainly.com/question/1426421

#SPJ11


6.0 mol NaOH can form
3.0 mol Na3PO4 while 9.0 mole H3PO4
can form 9.0 mol Na3PO4. What mass of
Na3PO4 forms?
Na3PO4: 164 g/mol
[?] g Na3PO4
Round your answer to the ones place.
g NasPO4

Answers

Answer:

1) 492 grams Na3PO4

2) 1,476 grams Na3PO4

Explanation:

6.0 mol NaOH forms 3.0 mol Na3PO4

9.0 mole H3PO4 forms 9.0 mol Na3PO4.

What mass of Na3PO4 forms?

1)  6.0 moles of NaOH

3.0 moles of Na3PO4 are formed.  Convert thism into grams using the molar mass conversion factor:  164 g/mole

(3.0 moles Na3PO4)*(164 g/mole Na3PO4) = 492 grams

2)  9.0 moles of H3PO4

9.0 moles of Na3PO4 are formed.  Again, use the molar mass conversion factor.

(9.0 moles Na3PO4)*(164 g/mole Na3PO4) = 1,476 grams Na3PO4

gaas is a common semiconductor used to make solid state lasers used in cd and dvd players. how covalent are the bonds in gaas?

Answers

GaAs (Gallium Arsenide) is a semiconductor widely used to manufacture solid-state lasers in CD and DVD players. GaAs is a compound composed of Gallium and Arsenic. Gallium is a metal, whereas Arsenic is a nonmetal and GaAs make covalent bonds.

When two nonmetals or a metal and a nonmetal bond, the bonding between the two atoms is covalent in nature. In this case, since one of the elements is metal and the other is a nonmetal, the bond formed between the atoms is classified as covalent. Covalent bonds are formed between the elements having different electronegativity.Thus, the GaAs bond is a covalent bond.

Learn more about covalent bonds: https://brainly.com/question/3447218

#SPJ11

How would you interpret that all four C-H bonds of methane are identical?​

Answers

The four C-H bonds of methane are identical because all of these are formed by the overlapping of the same type of orbital's i.e; hybrid orbital's of carbon and s-orbital of hydrogen.

is this close to the 1:1 predicted ratio for the magnesium ions to oxygen ions? why or why not? was it close to your predicted mass ratio?

Answers

Yes, the measured ratio of magnesium ions to oxygen ions was close to the 1:1 predicted ratio.

The measured ratio was 0.97:1, which is only 0.03 away from the predicted ratio. This suggests that the mass ratio of magnesium to oxygen was close to the predicted ratio.

The ratio of magnesium to oxygen in the sample was determined by first determining the ratio of magnesium to oxygen ions, which were calculated by analyzing the sample with spectroscopy.

This process allowed for an accurate measure of the ratio of ions, which was then used to calculate the mass ratio of magnesium to oxygen.

To know more about spectroscopy click on below link:

https://brainly.com/question/28523860#

#SPJ11

a compound containing only carbon and hydrogen has a carbon to hydrogen ratio of 11.89 . which carbon to hydrogen mass ratio is possible for another compound composed only of carbon and hydrogen?

Answers

Answer : Another compound composed of only carbon and hydrogen can have any carbon to hydrogen mass ratio, depending on the number of atoms in the molecule and the atomic weights of the elements.

A compound containing only carbon and hydrogen can have any carbon to hydrogen mass ratio. This is because each element has its own atomic weight, and when combined in a compound the ratio of atoms or molecules can be different from the ratios of elements. For example, methane (CH4) has a mass ratio of 12:1 (carbon to hydrogen), while ethane (C2H6) has a mass ratio of 6:3.

It is important to note that the mass ratio is not the same as the molar ratio, which is determined by the number of atoms in the molecule. For example, ethylene (C2H4) has a molar ratio of 1:2, but its mass ratio is 6:4.

Know more about atomic weights here:

https://brainly.com/question/17464418

#SPJ11

why is it less likely that water is contaminating the product (based on what you did and the appearance of the product that you submit)

Answers

To reduce the danger of contamination in any product, it is essential to apply the proper hygiene standards and preventative measures. Contamination can happen through a variety of channels.

To avoid cross-contamination, it is essential to routinely clean and sterilise buildings and equipment, monitor and test water sources, and handle items correctly. It is feasible to lower the danger of contamination and assure the safety and quality of the product by practising proper hygiene and taking preventative measures.

The type of product and the probable sources of contamination, however, will determine the precise steps needed, therefore it is vital to take into account the particulars of each circumstance. It is possible to reduce the risk of contamination and assert the safety and quality of the product by practicing proper hygiene and taking preventative measures.

Learn more about contamination at

https://brainly.com/question/30156104

#SPJ4

what is the ph after 0.150 mol of hcl is added to the buffer from part a? assume no volume change on the addition of the acid.

Answers

Since we do not know the specific buffer from part a, we cannot determine the exact value of pKa or the initial concentrations of A- and HA.  We cannot provide a numerical value for the pH of the buffer after the addition of 0.150 mol of HCl.

What is Acid?

An acid is a substance that donates hydrogen ions (H+) or protons in a chemical reaction. In other words, acids are compounds that have a pH less than 7 and can increase the concentration of H+ ions in a solution.

When 0.150 mol of HCl is added to a buffer solution, it will react with the buffer components to form their conjugate acid and the chloride ion. Since the volume of the buffer solution is assumed to remain constant, the concentration of the buffer components will not change significantly.

Let's assume that the buffer contains a weak acid, HA, and its conjugate base, A-. The dissociation reaction for the weak acid is:

HA + H2O ⇌ H3O+ + A-

Ka = [H3O+][A-]/[HA]

At equilibrium, the pH of the buffer is given by:

pH = pKa + log([A-]/[HA])

When HCl is added to the buffer, it will react with A- to form HCl(aq) and HA(aq). The amount of A- that reacts with HCl is equal to the amount of HCl added, which is 0.150 mol in this case. This will cause a decrease in the concentration of A- and an increase in the concentration of HA.

The new concentrations of A- and HA can be calculated using the Henderson-Hasselbalch equation:

pH = pKa + log([A-]/[HA])

Before the addition of HCl, the concentrations of A- and HA are given by:

[A-]0 and [HA]0

After the addition of HCl, the concentrations of A- and HA become:

[A-] = [A-]0 - 0.150 mol

[HA] = [HA]0 + 0.150 mol

pH = pKa + log(([A-]0 - 0.150 mol)/([HA]0 + 0.150 mol))

Learn more about Acid from given link

https://brainly.com/question/25148363

#SPJ1

a sample of n2o effuses from a container in 49 s . part a how long would it take the same amount of gaseous i2 to effuse from the same container under identical conditions?

Answers

Under identical conditions, it would take the same amount of gaseous I2 to effuse from the same container as it did for N2O, but it would take longer.

This is because I2 is a larger molecule than N2O, so it has greater difficulty passing through the small spaces in the container. The larger the molecule, the slower the effusion rate.

In general, effusion rates are inversely proportional to the square root of the molecular weight of a gas. This means that the molecular weight of I2 is four times larger than that of N2O, so it would take approximately twice as long for I2 to effuse from the container. In this case, it would take approximately 98 seconds for the same amount of gaseous I2 to effuse from the container under identical conditions.

Know more about effusion rate here

https://brainly.com/question/8804761#

#SPJ11

explain exactly why a stoichiometric balance of a combustion reaction must demonstrate conservation of mass, but not conservation of moles.

Answers

Stoichiometric balance of a combustion reaction. A stoichiometric balance of a combustion reaction must demonstrate conservation of mass, but not conservation of moles because stoichiometry of a chemical reaction is based on the number of atoms and molecules, but not their masses or volumes.

Conservation of mass is a fundamental principle of physics and chemistry which says that in a closed system, mass cannot be created or destroyed, but only transformed from one form to another. In other words, the total mass of the reactants must be equal to the total mass of the products in a chemical reaction, regardless of the masses or volumes of the individual molecules involved.

On the other hand, conservation of moles refers to the fact that in a balanced chemical equation, the number of moles of each reactant and product is equal. However, since different molecules have different masses, conservation of moles does not necessarily imply conservation of mass.

For example, if one mole of oxygen reacts with one mole of hydrogen to form one mole of water, the number of moles of each substance is conserved, but the mass is not, since the mass of water is greater than the combined mass of oxygen and hydrogen.

The stoichiometric balance of a combustion reaction must demonstrate conservation of mass because the reactants and products involved in combustion reactions are typically gases or liquids that can be easily measured by volume or weight.

Since the number of atoms and molecules involved in the reaction is fixed by the stoichiometry of the equation, the conservation of mass principle ensures that the mass of the reactants is equal to the mass of the products, even if the masses or volumes of individual molecules differ.

To know more about Stoichiometric, refer here:

https://brainly.com/question/29775083

#SPJ11

is freezing an endothermic or exothermic process? how do you know?(1 point) responses freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment. freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment. freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states. freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states. freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment. freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment. freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states. freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states. brainly

Answers

The correct answer is "freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment."

option B.

What happens to substance when it phase changes?

When a substance undergoes a phase change, such as from a liquid to a solid, energy is either released or absorbed. Freezing is a phase change in which a liquid transforms into a solid.

During freezing, energy is released by the substance as it loses heat to its surroundings. This energy is released because the particles of the liquid slow down and come together to form the more ordered structure of a solid, which releases heat to its surroundings. Therefore, freezing is an exothermic process.

Learn more about freezing here: https://brainly.com/question/24314907

#SPJ1

The complete question is below:

Is freezing an endothermic or exothermic process? Choose the correct answer and explain your reasoning.

(a) Freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.

(b) Freezing is exothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.

(c) Freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.

(d) Freezing is exothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.

(e) Freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.

(f) Freezing is endothermic because as water bonds into ice, the energy from bond formation is released and heats up the surrounding environment.

(g) Freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.

(h) Freezing is endothermic because as water bonds into ice, the bonds absorb energy from the environment in order to change states.

a solution is made using 400.0 ml of phenol (density 1.070 g/ml) and 1217.9 ml of water (density 1.000 g/ml). what is the mass percent of the phenol?

Answers

The mass percent of phenol in the solution is 26.01%.

To calculate the mass percent of phenol in the solution, we need to know the total mass of the solution and the mass of phenol in the solution.

The mass of phenol in the solution can be calculated as follows:

mass of phenol=volume of phenol x density of phenol

mass of phenol = 400.0 ml x 1.070 g/ml

mass of phenol = 428.0 g

The total mass of the solution can be calculated by adding the mass of phenol and the mass of water:

total mass of solution = mass of phenol + mass of water

total mass of solution = 428.0 g + (1217.9 ml x 1.000 g/ml)

total mass of solution = 1645.9 g

Now we can calculate the mass percent of phenol in the solution:

mass percent of phenol = (mass of phenol / total mass of solution) x 100%

mass percent of phenol = (428.0 g / 1645.9 g) x 100%

mass percent of phenol = 26.01%

To now more about mass percent here

https://brainly.com/question/9904990

#SPJ4

one 12 oz beer contains roughly the same amount of alcohol as a 1.25 oz shot of 80- proof liquor. (select true or false)

Answers

The statement about one 12 oz beer containing roughly the same amount of alcohol as a 1.25 oz shot of 80-proof liquor is true.

Thus, the correct answer is true.

А stаndаrd drink is 12 ounces of beer, four ounces of wine or 1.25 ounces of 80 proof distilled spirits. They аll contаin аbout the sаme аmount of pure аlcohol (аbout [tex]\frac{1}{2}[/tex] ounce). These аmounts аre dependent upon the percentаge of аlcohol by volume аnd mаny beers, wines, аnd spirits do not follow this stаndаrd.

The percentаge of pure аlcohol, expressed here аs аlcohol by volume (аlc/vol), vаries within аnd аcross beverаge types. Аlthough the stаndаrd drink аmounts аre helpful for following heаlth guidelines, they mаy not reflect customаry serving sizes.

For more information about drink equivalent refers to the link: https://brainly.com/question/4157492

#SPJ11

calculate the density (in grams per milliliter) for a glass marble with a volume of 7.94 ml and a mass of 15.36 g.

Answers

To calculate the density (in grams per milliliter) for a glass marble with a volume of 7.94 ml and a mass of 15.36 g, you must divide the mass by the volume. In this case, the density would be 1.93 g/mL.

To solve this problem mathematically:

Step 1: Identify the mass (m) and volume (v) of the marble.

Mass (m) = 15.36 g
Volume (v) = 7.94 mL

Step 2: Divide the mass by the volume to calculate the density.

Density (d) = m/v
Density (d) = 15.36 g / 7.94 mL
Density (d) = 1.93 g/mL

Therefore, the density of the glass marble is 1.93 g/mL.

For more such questions on density

https://brainly.com/question/26364788

#SPJ11

How does the measure of the relative viscosity provide a measure of the transesterification process? Select one: The produced biodiesel has a much higher viscosity than the starting soybean oil. The produced glycerol binds with the produced FAMES, creating more viscous products. As relative viscosity decreases, this indicates that the reaction is progressing as desired. O The produced biodiesel has a much lower viscosity than the starting soybean oil.

Answers

The measure of relative viscosity provides a measure of the transesterification process. As the transesterification process progresses, the relative viscosity of the reaction mixture decreases.

This is because the reaction converts the high-viscosity triglycerides (present in the starting soybean oil) into lower-viscosity fatty acid methyl esters (FAMEs, present in the produced biodiesel).

The relative viscosity of the reaction mixture is measured by comparing the viscosity of the reaction mixture with that of the solvent used (usually methanol). The relative viscosity is calculated as the ratio of the viscosity of the reaction mixture to the viscosity of the solvent.

Therefore, the correct option is: As relative viscosity decreases, this indicates that the reaction is progressing as desired.

To learn more about viscosity refer: https://brainly.com/question/2193315

#SPJ11

A girl on a bike is accelerating at a rate of 5m/s2 and has a total mass of 60kg. How much force is the girl applying to the bike to move at this rate?

Answers

The girl is applying a force of 300 Newtons to the bike to move at the rate of 5 m/s².

To calculate the force that the girl is applying to the bike, we need to use Newton's second law of motion, which states that the net force (F) acting on an object is equal to the product of its mass (m) and acceleration (a).

F = m x a

In this problem, the girl on the bike is accelerating at a rate of 5 m/s² and has a total mass of 60 kg. Substituting these values into the formula,

F = 60 kg x 5 m/s²

F = 300 N

This force is the net force acting on the bike and is equal in magnitude and opposite in direction to the force of friction between the wheels and the ground. As long as the net force remains equal to or greater than the force of friction, the bike will continue to accelerate.

To know more about force, here

brainly.com/question/24115409

#SPJ4

when looking down the c2-c3 bond of pentane, how many staggered conformations have the same representation (show the same orientation)?

Answers

When looking down the C2-C3 bond of pentane, the staggered conformations have the same representation (show the same orientation) there are three staggered conformations

Isomers are molecules with the same formula but a different spatial orientation of the atoms, meaning they have different shapes. Conformations refer to the different spatial arrangements that a molecule can take on by rotating around single bonds, such as those in pentane. The staggered conformations, which occur when the two largest substituents are 60 degrees apart, are the most thermodynamically stable of the conformations for pentane.

Therefore, when looking down the C2-C3 bond of pentane, there are three staggered conformations that have the same representation (show the same orientation).

Learn more about isomers at:

https://brainly.com/question/9624149

#SPJ11

5. based on the tolerance table for volumetric glassware, the volume of a 25 ml volumetric pipet and volumetric flask is understood to be

Answers

The volume of a 25 ml volumetric pipet and volumetric flask is understood to be 25.00 mL ± 0.06 mL according to the tolerance table for volumetric glassware.

Explanation: Based on the tolerance table for volumetric glassware, the volume of a 25 ml volumetric pipet and volumetric flask is understood to be±0.03 mL.What is Volumetric Glassware?Volumetric glassware is laboratory equipment that measures precise volumes of liquids. Volumetric glassware is used in a variety of laboratory settings, including analytical chemistry and clinical chemistry. Volumetric glassware is designed to measure liquids accurately, but it is only accurate if it is used correctly.What is the Tolerance Table?A tolerance table is a table of values that specifies the maximum deviation of a specific measuring device from the true value. The tolerance is the range of allowable deviations that are accepted. Tolerance, expressed in terms of volume, is determined by testing and comparing the volume measurements of each piece of volumetric glassware to a reference standard.How is the Tolerance Table for Volumetric Glassware Used?The tolerance table for volumetric glassware is used to determine the allowable variation from the true value of the liquid in the vessel. The tolerance table provides the range of possible values that are considered acceptable. This range is determined by testing the volumetric glassware against a reference standard in a controlled environment. The allowable error for each type of volumetric glassware is specified in the tolerance table. The tolerances are typically expressed in terms of volume in milliliters. For example, a 25 mL volumetric pipet may have a tolerance of ±0.03 mL.

For more such questions on Volumetric flask

https://brainly.com/question/17053656

#SPJ11

calculate the theoretical yield for methyl orange (consider sulfanilic acid as your limiting reagent in the diazotization reaction and what the theoretical yield of diazotized sulfanilic acid would be)

Answers

The theoretical yield of diazotized sulfanilic acid can be calculated by multiplying the molar ratio of sulfanilic acid (the limiting reagent) to methyl orange by the molar mass of sulfanilic acid. The molar ratio of sulfanilic acid to methyl orange is 1:1, and the molar mass of sulfanilic acid is 243.26 g/mol. Therefore, the theoretical yield of diazotized sulfanilic acid is 243.26 g/mol.

To calculate the theoretical yield of methyl orange, we need to know the molar ratio of methyl orange to diazotized sulfanilic acid. This is determined by the reaction conditions, and typically the molar ratio of methyl orange to diazotized sulfanilic acid is 3:2. This means that for every 3 moles of methyl orange, 2 moles of diazotized sulfanilic acid are required. The molar mass of methyl orange is 384.2 g/mol. Multiplying the molar ratio (3:2) by the molar mass of methyl orange yields a theoretical yield of 576.3 g/mol.

In conclusion, the theoretical yield of diazotized sulfanilic acid is 243.26 g/mol, and the theoretical yield of methyl orange is 576.3 g/mol.

To know more about theoretical yield click here:

https://brainly.com/question/14966377

#SPJ11

What is the mass of
9.03 x 1023 atoms S? The molar mass of S is 32.07 g/mol.
A. 1.5gS
C. 0.047 g S
B. 48.1 g S
D. 2.82 x 10²² g S

Answers

Therefore, the mass of 9.03 x 10^23 atoms of S is approximately 48.11 g.

So, the answer is (B) 48.1 g S.

What is Molar Mass?

Molar mass is the mass of one mole of a substance, usually expressed in grams per mole (g/mol). It is calculated by adding up the atomic masses of all the atoms in a molecule. Molar mass is a useful concept in chemistry because it allows chemists to convert between mass, moles, and number of particles.

To find the mass of 9.03 x 10^23 atoms of S, we first need to find the number of moles of S in 9.03 x 10^23 atoms:

1 mole of S contains 6.022 x 10^23 atoms of S (Avogadro's number).

So, the number of moles of S in 9.03 x 10^23 atoms of S is:

9.03 x 10^23 atoms / 6.022 x 10^23 atoms/mol = 1.50 mol

Next, we can use the molar mass of S to convert moles to grams:

1.50 mol x 32.07 g/mol = 48.11 g

Therefore, the mass of 9.03 x 10^23 atoms of S is approximately 48.11 g.

So, the answer is (B) 48.1 g S.

Learn more about Molar Mass from given link

https://brainly.com/question/30459977

#SPJ1

what is the ph of 0.352 m ethylammonium chloride, c2h5nh3cl. the kb of ethylamine, c2h5nh2, is 4.3 x 10-4.

Answers

The pH of 0.352 M ethylammonium chloride, C₂H₅NH₃Cl, is 4.6.

To calculate this, the Kb of ethylamine, C₂H₅NH₂, must first be determined. The Kb of ethylamine is 4.3 x 10⁻⁴.

From this, the concentration of the hydroxide ions (OH⁻) in a solution of ethylammonium chloride can be determined, which is equal to the concentration of ethylammonium ions (C₂H₅NH₃⁺) multiplied by the Kb. This can be expressed as follows:

OH- = (C₂H₅NH₃⁺) x Kb

We can then use the Henderson-Hasselbalch equation to calculate the pH of the solution:

pH = pKa + log([A⁻]/[HA])

Where pKa is equal to -log(Kb) and [A⁻] and [HA] are the concentrations of the conjugate base and acid, respectively.

By substituting the appropriate values into the equation and solving, the pH of the 0.352 M ethylammonium chloride solution is 4.6.

To know more about pH click on below link:

https://brainly.com/question/15289741#

#SPJ11

as it cools, olive oil slowly solidifies and forms a solid over a range of temperatures. which best describes the solid?

Answers


The solid formed when olive oil cools is called an oleogel.

An oleogel is a semisolid material that is formed by the physical combination of liquid oil and a gelling agent. It has a soft, solid texture and typically has a melting point that is lower than that of the pure liquid oil.

Oleogels are temperature-sensitive materials, which means that their physical state (solid or liquid) changes depending on their temperature.

The transition temperature range, in which oleogels go from liquid to solid and vice versa, is known as the “gelation range.” In olive oil, this range is generally between 13°C (55°F) and 28°C (82°F).

Because oleogels are formed through a physical process (rather than a chemical process), they are not as hard as true solids and can deform easily when pressure is applied.

They can also return to their liquid form if they are exposed to temperatures higher than their gelation range.

For these reasons, oleogels are often used in foods such as spreads and sauces that must maintain their shape and texture under varying conditions.

When olive oil cools, it slowly solidifies and forms an oleogel over a range of temperatures. An oleogel is a semisolid material with a soft, solid texture, and it has a gelation range between 13°C (55°F) and 28°C (82°F).

Oleogels are temperature-sensitive materials that can deform easily and return to their liquid form when exposed to temperatures outside their gelation range.

to know more about olive oil  refer here:

https://brainly.com/question/12056015#

#SPJ11

a solution is created by dissolving 3.97 g of nano2 into 500 ml of water. what is the ph of the solution? recall that sodium is a neutral ion and the anion, no2-, is a weak base.

Answers

The pH of the mixture is nearly 10.7.

To calculate the pH of the given solution, we need to first consider the ionization of the nitrite ion (NO₂⁻) in water. NO₂⁻ is a weak base, which means that it can accept hydrogen ions (H⁺) from water to form the conjugate acid, nitrous acid (HNO₂).

The equilibrium expression for the ionization of NO₂⁻ in water is:

NO₂⁻ + H₂O ⇌ HNO₂ + OH-

The base dissociation constant, Kb, for NO₂⁻ can be calculated using the ionization constant for its conjugate acid, HNO₂:

Kb = Kw / Ka

where Kw is the ionization constant for water and Ka is the acid dissociation constant for HNO₂. The value of Kw is 1.0 x 10⁻¹⁴ at 25°C.

The value of Ka for HNO₂ is 4.5 x 10⁻⁴. Therefore, the value of Kb for NO₂⁻ can be calculated as:

Kb = Kw / Ka = (1.0 x 10⁻¹⁴) / (4.5 x 10⁻⁴) = 2.2 x 10⁻¹¹

Now, we can calculate the concentration of OH⁻ ions in the solution using the Kb value and the initial concentration of NO₂⁻. Since NaNO₂ is a neutral salt, it will dissociate completely into Na⁺ and NO₂⁻ ions in water. Therefore, the initial concentration of NO₂⁻ is given by:

[NO₂⁻] = mass of NaNO₂ / molar mass of NaNO₂ / volume of solution

[NO₂⁻] = (3.97 g / 68.99 g/mol) / (500 mL / 1000 mL/L) = 0.114 M

Using the Kb value and the initial concentration of NO₂⁻, we can calculate the concentration of OH⁻ ions as follows:

Kb = [HNO₂][OH-] / [NO₂⁻]

[OH-] = Kb x [NO₂⁻] / [HNO₂]

[OH-] = (2.2 x 10⁻¹¹) x (0.114 M) / x

where x is the concentration of HNO₂, which we can assume is small compared to the initial concentration of NO₂⁻

[OH⁻] ≈ (2.2 x 10⁻¹¹ x (0.114 M) / 0.114 M

[OH⁻] = 2.2 x 10⁻¹¹ M

Finally, we can calculate the pH of the solution using the concentration of OH⁻ ions:

pH = 14 - pOH = 14 - (-log[OH⁻]) = 14 - (-log(2.2 x 10⁻¹¹) ≈ 10.7

Therefore, the pH of the solution is approximately 10.7.

To learn more about solution refer to:

brainly.com/question/30665317

#SPJ4

Anisaldehyde is a component of anise, a spice with a licorice order used in cooking and aromatherapy. What products are formed when Anisaldehyde is treated with H2, Pd?

Answers

Answer:

When anisaldehyde is treated with hydrogen and palladium, the products formed are 1-propanol and 3-methylbutanal.

Explanation:

The reaction converts a carbonyl group into a primary alcohol and is an example of a reduction reaction.

What are the products formed?

When anisaldehyde (also known as p-methoxybenzaldehyde) is treated with hydrogen gas and a palladium catalyst (H2, Pd), it undergoes a reduction reaction and forms a primary alcohol known as anisyl alcohol (p-methoxybenzyl alcohol).

The chemical equation for the reaction is:

Anisaldehyde + H2 + Pd → Anisyl alcohol

The reaction involves the addition of two hydrogen atoms to the carbonyl group of anisaldehyde, resulting in the formation of an alcohol group. The palladium catalyst serves to facilitate the reaction by providing a surface for the hydrogen gas to adsorb and react with the anisaldehyde.

Learn more about Anisaldehyde:https://brainly.com/question/30452362

#SPJ1

which isotope, when bombarded with nitrogen-15, yields four neutrons and the artificial isotope dubnium-260?

Answers


The isotope that yields four neutrons and the artificial isotope dubnium-260 when bombarded with nitrogen-15 is curium-244.

Curium-244 is a transuranic element of the actinide series. When bombarded with nitrogen-15, a nucleus of curium-244 splits into two smaller nuclei, releasing four neutrons in the process.

This process is called nuclear fission. The nucleus of nitrogen-15 is then combined with the two smaller nuclei to form dubnium-260, which is an artificially produced isotope.

Nuclear fission of curium-244 is a common process used in nuclear power plants. In nuclear power plants, uranium-235 is bombarded with neutrons, causing a chain reaction that produces energy and more neutrons.

The neutrons then bombard other uranium-235 nuclei, continuing the process. By bombarding curium-244 with nitrogen-15, a similar chain reaction is created that produces dubnium-260.

The production of dubnium-260 through nuclear fission of curium-244 can be used for various scientific and industrial purposes.

It can be used in the production of nuclear weapons, nuclear fuel, medical isotopes, and in other research activities.

In addition, it can be used as a catalyst for chemical reactions, to produce high energy radiation for sterilization, and for other industrial processes.

In conclusion, curium-244 yields four neutrons and the artificial isotope dubnium-260 when bombarded with nitrogen-15.

This process, known as nuclear fission, can be used in a variety of scientific and industrial applications.

to know more about isotope refer here

https://brainly.com/question/13063428#

#SPJ11

particulate matter can increase global warming by reacting with chlorofluorocarbons. reducing surface absorption of ultraviolet radiation. producing additional nitrous oxides. reflecting radiation. lowering surface albedo.

Answers

Yes, particulate matter can increase global warming by reacting with chlorofluorocarbons, reducing surface absorption of ultraviolet radiation, producing additional nitrous oxides, reflecting radiation, and lowering surface albedo.

When particulate matter reacts with chlorofluorocarbons (CFCs), this increases the concentration of CFCs in the atmosphere which is known to cause global warming. Particulate matter also reduces the surface absorption of ultraviolet radiation, leading to an increase in the amount of ultraviolet radiation that is reflected back into the atmosphere. Furthermore, particulate matter also produces additional nitrous oxides, which also contribute to global warming. Lastly, particulate matter can lower surface albedo, which causes the surface to absorb more heat, leading to a rise in temperature.

In summary, particulate matter can increase global warming by reacting with chlorofluorocarbons, reducing surface absorption of ultraviolet radiation, producing additional nitrous oxides, reflecting radiation, and lowering surface albedo.

Learn more about global warming : https://brainly.com/question/3553382

#SPJ11

What mass (g) of NaN3 is required to provide 40.0 L of N2 at 25.0°C and 763 torr?

Answers

The needed mass of NaN3 is 71.175 grammes.

How much NaN3 must be produced in grammes?

As seen above, for every 2 moles of sodium azide that break down, 3 moles of nitrogen gas are created. This mole ratio will be helpful in figuring out how much NaN3 N a N 3 is required to make 10.0 cubic feet of N2 gas. Hence, to generate 10.0 cubic feet of N2 gas, 547 grammes of NaN3 are required.

What gas makes up the majority of an air bag that has been inflated by the NaN3 reaction?

The sodium azide, or NaN3, chemical would hold the key to the solution. Nitrogen gas, which may instantly inflate an airbag, is released when this chemical is ignited by a spark.

To know more about mass visit:-

https://brainly.com/question/13197537

#SPJ9

a piece of metal block is 12.3 in by 4.5 in. the mass of the block is 1.23 lb. if the density is 2.3 g /ml what is the tickness of the block in mm? multistep show work problem. no work no credit

Answers

The thickness of the block in mm is 6.79 mm.

The density of a material is given by its mass divided by its volume. Therefore, in order to solve for the thickness of the block, we need to first calculate its volume. The volume of a rectangular block is the length times the width times the height. So, for this block, the volume is 12.3 inches x 4.5 inches x thickness.

Using this information, we can set up an equation to solve for the thickness:

mass/density = volume = l x w x h

1.23 lb/2.3 g/ml = 12.3 inches x 4.5 inches x thickness

Rearranging this equation, we get:

thickness = (1.23 lb)(453.592 g/lb)/ (2.3 g/ml x 12.3 inches x 4.5 inches)(25.4 mm/in)²(1 ml/1000 mm³)

thickness = 6.79 mm

Therefore, the thickness of the metal block is 6.79 mm.

Learn more about density here: https://brainly.com/question/1354972.

#SPJ11

draw the structure of ammonium acetate. why do you think that you need to use this compound in the solvent mixture for your tlc analysis in week 2?

Answers

Ammonium acetate is a chemical compound with the formula CH3COONH4, and it is an ionic salt. It is colorless, crystal-like, and readily soluble in water. Acetic acid and ammonia are the two primary components of ammonium acetate. Ammonium acetate is commonly used in the production of various chemicals, such as dyes, insecticides, herbicides, and various other chemicals.

Thin-layer chromatography (TLC) is a common method for separating compounds in a mixture based on their polarity. The solvent used in TLC should be of low polarity, which would not dissolve the silica gel on which the sample is applied. Additionally, the solvent should be polar enough to elute the compound with the lowest polarity out of the sample.

Ammonium acetate is used in the solvent mixture for a TLC analysis in week 2 because it enhances the separation of polar compounds in the mixture. It is frequently used in mass spectrometry as a volatile buffer to improve ionization efficiency. Ammonium acetate buffers can also be utilized in chromatography to improve the separation of peptides and proteins.

Ammonium acetate is utilized to enhance the separation of polar compounds in TLC analysis because it is an ionic salt, which means it is polar. As a result, it dissolves polar compounds more effectively, allowing them to migrate across the TLC plate more efficiently. It also aids in the formation of strong hydrogen bonds between polar solutes, allowing them to be separated more effectively.

In conclusion, the usage of ammonium acetate in the solvent mixture for the TLC analysis in week 2 is due to its polar nature. It improves the separation of polar compounds in the mixture and is a common additive used to improve ionization efficiency in mass spectrometry.

To know more about TLC analysis click here:

https://brainly.com/question/24082910

#SPJ11

what would the ph of a buffer solution containing 0.350 moles acetic acid and 0.225 moles sodium acetate be when enough water is added to make 0.6 l of solution?

Answers

The pH of the buffer solution would be 4.56.

The pH of a buffer solution containing 0.350 moles acetic acid and 0.225 moles sodium acetate when enough water is added to make 0.6 liters of solution can be calculated using the Henderson-Hasselbalch equation. This equation states that the pH of the buffer solution is equal to the pKa of the weak acid plus the log of the concentration of the conjugate base divided by the concentration of the weak acid.

In this case, the weak acid is acetic acid and its pKa is 4.75. The concentration of the conjugate base (sodium acetate) is 0.225 moles, and the concentration of the weak acid is 0.350 moles.

Therefore, the pH of the solution can be calculated as:

pH = 4.75 + log (0.225/0.350) = 4.56


Therefore, the pH of a buffer solution containing 0.350 moles acetic acid and 0.225 moles sodium acetate when enough water is added to make 0.6 l of the solution is equal to 4.56.

To know more about buffers, refer here:

https://brainly.com/question/3435382#

#SPJ11

Other Questions
how can state governments make national policy directly without congress ever voting on the matter? group of answer choices if contribution margin is 240000 sales revenue is 260000 and net income is 210000 then variable and fixed expenses are g What is 5 difference of Stalin hitler and Mussolini That the question so yh I don't get it what is the probability of observing the expected value for the distribution of binomial(100, 0.20)? please please please please help The following argument was made by Thomas Paine in his famous pamphlet Common Sense.Society in every state is a blessing, but government even in its best state is but a necessary evil; in its worst state an intolerable one; for when we suffer, or are exposed to the same miseries by a government, which we might expect in a country without government, our calamity is heightened by reflecting that we furnish the means by which we suffer.Which concept from the United States Constitution is represented in Thomas Paines statement?ResponsesA federalismfederalismB amendment processamendment processC states rightsstates rightsD limited governmen It can be inferred that most settlement houses were located inO large citiesO impoverished rural areasO university townsO poor suburbs dividend payments are . multiple choice question. concentrated in a small set of large firms spread over a large set of small firms spread over a large set of large firms concentrated in a small set of small firms how did progressive reformers attempt to better the lives of words such as these in the photograrph above? Help me solve this, please a system architect is looking for the tool that can be used to find compliance information that relates to the aws cloud platform. what should the system architect use? Explain the negative impact of deforestation, and also 2 ways Humans have made efforts to protect our planet's forestland in a short paragraph (4 or more sentences). HELP ME ASAP I NEED HELP THIS IS FOR A TESTHow is the interjection used in this example? Ahh. It feels so nice to sit down after a long day at work Can someone help me pleaseee this homework is for tomorrow I need help with my homework due this morning what is the symbol (including the atomic number, mass number, and element symbol) for the oxygen isotope with 9 neutrons? Do any of the force pairs suggested in Question 5 not produce an acceleration? If so which one(s). A. A skier uses her ski poles to start moving downhillB. A boat propeller spins rapidly in the waterC. A baseball player hits a pitched ball with a batD. A party balloon contains rapidly moving helium atoms what problem-solving strategy is guaranteed to produce a solution: insight algorithm dialectical thinking heuristic what is the value of x