Which of the following compounds are held together by ionic bonds? Select all that apply.

A gas of unknown molecular mass was allowed to effuse through a small opening under constant-pressure conditions. It required 10

Shtirlitz [24]

Answer:

The molar mass of the unknown gas is 392 g/mole

Explanation:

Firstly we write out the parameters

Volume of the gas X that effuse for 105 s = 1.0 L

Volume of the O₂ gas that effuse for 30 s = 1.0 L

Molar mass of O₂ = 32 g/mole

Rate of effusion of the gas X = 1.0 L/105 s = 0.0095 L/s

Rate of effusion of O₂ gas = 1.0 L/30 s = 0.033 L/s

Graham's law of effusion states that

$\frac{Rate A}{Rate B} = \sqrt{\frac{Molar mass B}{Molar mass A} }$

Therefore we have

$\frac{0.0095 L/s}{0.033 L/s} =\sqrt{\frac{32 g/mole}{Molar mass of X} }$ or Molar mass of X = $\frac{32}{0.0816}$ g/mole = 391.99 g/mole

The molar mass of the unknown gas is 391.99 g/mole ≈ 392 g/mole

8 0

3 years ago

er solutions can be produced by mixing a weak acid with its conjugate base or by mixing a weak base with its conjugate acid. The

liubo4ka [24]

Answer:

You need to add 19,5 mmol of acetates

Explanation:

Using the Henderson-Hasselbalch equation:

pH = pKa + log₁₀ [base]/[acid]

For the buffer of acetates:

pH = pKa + log₁₀ [CH₃COO⁻]/[CH₃COOH]

As pH you want is 5,03, pka is 4,74 and milimoles of acetic acid are 10:

5,03 = 4,74 + log₁₀ [CH₃COO⁻]/[10]

1,95 = [CH₃COO⁻]/[10]

<em>[CH₃COO⁻] = 19,5 milimoles</em>

Thus, to produce an acetate buffer of 5,03 having 10 mmol of acetic acid, you need to add 19,5 mmol of acetates.

I hope it helps!

7 0

4 years ago

A metal ion (X) with a charge of 2+ is attracted to a nonmetal ion (Z) with a charge of 3-.Which formula represents the resultin

Viefleur [7K]

Answer:

X₃Z₂

Explanation:

A metal ion (X) with a charge of 2+ = X²⁺

nonmetal ion (Z) with a charge of 3- = Z³⁻

In a neutral compound, the charges but balance each other to remain neutral. However in this case, the charges are not balanced.

A simple way to make the charges balance is by tweaking the number of the ions present in the compound.

We do this by multiplying the metal ion with 3 and the non metal ion by 2.

That way we have;

Metal ion = 3X2⁺ (Total charge - 6⁺)

Non metal ion = 2Z3⁻ (Total charge - 6⁻)

The charges are now balanced. The formular of the compound is;

X₃Z₂

5 0

3 years ago

Read 2 more answers

What are the two energy of the electrons outside the nucleus

ICE Princess25 [194]

Answer:

Unlike protons and neutrons, which are located inside the nucleus at the center of the atom, electrons are found outside the nucleus. Because opposite electric charges attract each other, negative electrons are attracted to the positive nucleus

8 0

3 years ago

Explain the concept of thekinetic molecular theory

disa [49]

Answer:

Kinetic Molecular Theory states that gas particles are in constant motion and exhibit perfectly elastic collisions. Kinetic Molecular Theory can be used to explain both Charles' and Boyle's Laws. The average kinetic energy of a collection of gas particles is directly proportional to absolute temperature only.

Explanation:

hope this helps! goodluck & enjoy the rest of ur day or night.

4 0

3 years ago