QA 4 Online Review

What is the molarity of a solution that contains 0.400 mol HCl in 9.79 L solution?

(a)  

Suppose 163.9 g of Na₃PO₄ in solution mixed with sufficient CaCl₂ in solution and yields 116 g of Ca₃(PO₄)₂(s). What is the percent yield of Ca₃(PO₄)₂(s)?

(a)  

The concentration of hydrogen ions in an aqueous solution is 1.0 × 10^-5 M at 298 K. What is the concentration of hydroxide ions in the same solution?

(a)  

When sulfuric acid is combined with sugar, gas is released and a tall, black column forms. This is an example of a:

• physical property

• physical change

• chemical property

• chemical change

Substances with an indefinite shape and an indefinite volume are in which state of matter?

• solid

• liquid

• gas

• none of the above

A student is conducting an experiment at STP where a solid metal is reacting with an acid solution to produce a hydrogen gas as seen above. This gas is then collected in a eudiometer, and its volume is measured to be 112 milliliters. How many moles of hydrogen gas have been collected?

(a)  

If you use 100.0 grams of calcium phosphate and an excess of silicon dioxide and carbon, how many moles of phosphorus will be produced?

2 Ca₃(PO₄)₂ +6 SiO₂ + 10 C --> 6 CaSiO₃ + P₄ + 10 CO

(a)  

Suppose 110.0 g of CaCl₂ in solution is mixed with 163.9 g of Na₃PO₄ in solution. How much Ca₃(PO₄)₂(s) would be produced?

3 CaCl₂ (aq) + 2 Na₃PO₄ (aq) --> Ca₃(PO₄)₂ (s) + 6 NaCl (aq)

(a)  

Which of the following is a physical change?

• H₂O (s) --> H₂O (l)

• NaCl (s) --> Na⁺¹ (aq) + Cl^-1 (aq)

• C₆H₁₂O₆ + 6 O₂ --> 6 CO₂ + 6 H₂O

• CO₂ (s) --> CO₂ (g)

A chemist prepared a solution of NaOH by completely dissolving 55.90 grams of solid NaOH in 3.600 liters of water at room temperature. What was the pH of the solution that the chemist prepared?

(a)