Which of these describes a physical change? Choose the correct answer. You may only choose one. A. Wood logs are burned in a fire.

B. Coconut oil begins to crystallize after being placed in a freezer.

C. Milk left out of the refrigerator for a week starts to smell different.

D. Sodium hydroxide and hydrochloride acid are mixed in water to form a salt.

7.28 mol Na2SO4

Explanation:

Since it is already in moles, all we have to do is use a molar ratio

A molar ratio is the proportions of reactants and products using the balanced equation. When writing a mole ratio, the given information must cross out with the right thing.

7.28 mol H2SO4 * 1 mol Na2SO4/1 H2SO4 = 7.28 mol Na2SO4

*notice how the H2SO4 crosses out