6.25 g of HCl(g), a strong acid, is dissolved in water to make a 280-ml solution.

A solution is made by adding 29.1 mL of concentrated perchloric acid ( 70.5 wt% , density 1.67 g/mL ) to some water in a volumet

Lera25 [3.4K]

Answer:

The concentration of the solution is 1.364 molar.

Explanation:

Volume of perchloric acid = 29.1 mL

Mass of the solution = m

Density of the solution = 1.67 g/mL

$m=1.67 g/mL\times 29.1 mL=48.597 g$

Percentage of perchloric acid in 48.597 solution :70.5 %

Mass of perchloric acid in 48.597 solution :

= $\frac{70.5}{100}\times 48.597 = 34.261 g$

Moles of perchloric acid = $\frac{34.261 g}{100.46 g/mol}=0.3410 mol$

In 29.1 mL of solution water is added and volume was changed to 250 mL.

So, volume of the final solution = 250 mL = 0.250 L (1 mL = 0.001 L)

$Molarity=\frac{Moles}{Volume (L)}$

$=\frac{0.3410 mol}{0.250 L}=1.364 M$

The concentration of the solution is 1.364 molar.

6 0

3 years ago

Given the unbalanced equation: PbCl₂ + Na₂CrO₂ ---> PbCrO₂ + NaCl. When properly balanced, the sum of the balancing coefficie

Veronika [31]

Answer:

A. 2

hope this helps :)

if you need an explanation let me know!!

3 0

3 years ago

Hi!! please help :( lots of points !

andreev551 [17]

Answer:

Structure:

Differences- A polymer is a collection of a large number of molecules whereas a monomer is a single molecule.

A monomer is a single molecule, which has the ability to chemically bond with other monomers in a long chain. A polymer is a chain that is made when monomers bind with other monomers.

Similarities- They are both molecules

Properties:

Differences- Monomers have polyfunctionality, which is the capacity to form chemical bonds to at least two other monomer molecules. Polymers are chemically unreactive, solids at room temperature, malleable, tough, and are electrical insulators.

Similarities- They both makeup larger forms of matter.

Intermolecular Forces

Differences: Polymers are held together by covalent bonds, hydrogen bonds, and dispersion bonds. Monomers are only held together by hydrogen bonds.

Similarities: They can both be bonded together by hydrogen bonds.

3 0

1 year ago

In the experiment, 40 mL of 3 M sodium hydroxide is used to extract the benzoic acid. In order to recover the benzoic acid from

nikdorinn [45]

Answer:

20 mL OF 6 M HYDROCHLORIC ACID WILL BE NEEDED

Explanation:

M1 V1 = M2 V2

M1 = Molarity of sodium hydroxide = 3 M

V1 = volume of sodium hydroxide = 40 mL

M2 = Molarity of hydrochloric acid = 6 M

V2 = Volume of hydrochloric acid = unknown

Rearranging the equation, we have:

V2 = M1 V1 / M2

V2 = 3 * 40 mL / 6

V2 = 120 / 6

V2 = 20 mL

To precipitate the benzoic acid by 6 M of hydrochloric acid, 20 mL volume will be needed.

6 0

3 years ago

(b) Once the ionic solid has dissolved, the anion that is formed is able to react as a base, with water as the acid. Write the n

Marrrta [24]

Answer:

b C₂H₃O₂⁻ + H₂O ⇄ HC₂H₃O₂ + OH⁻

e HC₂H₃O₂ + H₂O ⇄ H₃O⁺ + C₂H₃O₂⁻

f ka<<1

g. Weak acid molecules and water molecules

Explanation:

The water molecule could act as a base and as an acid, a molecule that have this property is called as amphoteric.

b The salt NaC₂H₃O₂ is dissolved in water as Na⁺ and C₂H₃O₂⁻. The reaction of the anion with water is:

C₂H₃O₂⁻ + H₂O ⇄ HC₂H₃O₂ + OH⁻

Where the C₂H₃O₂⁻ is the base and water is the acid.

e. The reaction of HC₂H₃O₂ (acid) with water (base), produce:

HC₂H₃O₂ + H₂O ⇄ H₃O⁺ + C₂H₃O₂⁻

f. As the acetic acid (HC₂H₃O₂) is a week acid, the dissociation in C₂H₃O₂⁻ is not complete, that means that ka<<1

g. The ka for this reaction is 1,8x10⁻⁵, that means that there are more weak acid molecules (HC₂H₃O₂) than conjugate base ions. Also, the water molecules will be in higher proportion than hydronium ions.

I hope it helps!

4 0

3 years ago