In the compound MgCl2, the subscript 2 indicates thata. there are two magnesium ions for each ion of chlorine
b. the chloride ion is twice the size of the magnesium ion.
c. magnesium and chlorine form a double covalent bond.
d. there are two chloride ions for each magnesium ion.

Answer:

• The third chice: 0.0750 M Na₂SO₄

Explanation:

Assume 100% ionization:

1) 0.100 M solution K₂SO₄

• K₂SO4 (aq) → 2K⁺ (aq) + SO₄²⁻ (aq)

• Mole ratios: 1 mol K₂SO4 : 2 mol K⁺  + 1 mol SO₄²⁻ (aq) : 3 mol ions. This is 1 : 3

• At constant volume, the mole ratios are equal to the concentration ratios (M).

• 1  M K₂SO₄: 3 M ions = 0.100 M K₂SO₄ / x ⇒ x = 0.300 M ions

This means, that you have to find which of the choices is a solution that contains the same 0.300 M ion concentration.

2) 0.0800 M Na₂CO₃

• Na₂CO₃ (aq) → 2 Na⁺ + CO₃⁻

• 1 M Na₂CO₃ / 3 M ions = 0.0800M / x ⇒ x = 0.0267 M ions

This is not equal to 0.300 M, so this solution would not contain the same total concentration as a 0.100 M solution of K₂SO₄, and is not the right answer.

3)  0.100 M NaCl

• NaCl → Na⁺ + Cl⁻

• 1 M NaCl / 2 M ions = 0.100 M NaCl / x ⇒ x = 0.200 M ions

This is not equal to 0.300 M ion, so not a correct option.

4) 0.0750 M Na₃PO₄

• Na₃PO₄ → 3Na⁺ + PO₄³⁻

• 1 M Na₃PO₄ / 4 M ions = 0.0750 M Na₃PO₄ / x ⇒ x = 0.300 M ions

Hence, this ion concentration is equal to the ion concentration of a 0.100 M solution of K₂SO₄, and is the correct choice.

5)  0.0500 M NaOH

• NaOH → Na⁺ + OH⁻

• 1 M NaOH / 2 mol ions = 0.0500 M NaOH / x ⇒ x = 0.100 M ions

Not equal to 0.300 M, so wrong choice.

Answer:

1)  Ethanol

Explanation:

If we will have interactions we will need more energy to break them in order to go from liquid to gas. If we need more energy, therefore, the temperature will be higher.

In this case, we can discard the propanone because this molecule don't have the ability to form hydrogen bonds. (Let's remember that to have hydrogen bonds we need to have a hydrogen bond to a heteroatom, O, N, P or S).

Then we have to analyze the hydrogen bonds formed in the other molecules. For ethanol, we will have only 1 hydrogen bond. For water and ethanoic acid, we will have 2 hydrogen bonds, therefore, we can discard the ethanol.  

For ethanoic acid, we have 2 intramolecular hydrogen bonds. For water we have 2 intermolecular hydrogen bonds, therefore, the strongest interaction will be in the ethanoic acid.

The closer boiling point to the 75ºC is the ethanol (boiling point of 78.8 ºC) therefore these molecules would have enough energy to break the hydrogen bonds and to past from liquid to gas.

Final answer:

Among Ethanoic Acid, Ethanol, Propanone, and Water, Propanone has the highest vapor pressure at 75°C because it has the weakest intermolecular forces, making it more likely to vaporize.

Explanation:

The vapor pressure of a substance is determined by how easily particles can escape from the liquid phase and become a gas. In general, the higher the temperature, the higher the vapor pressure.

The four liquids provided in your question are Ethanoic Acid, Ethanol, Propanone, and Water. At 75°C, Propanone is known to have the highest vapor pressure among the listed substances. This is because Propanone, also known as acetone, has weaker intermolecular forces and thus more readily vaporizes.

Learn more about Vapor Pressure here:

brainly.com/question/34135527

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