Choose one answer for each question: 1.) Increasing the pressure of oxygen above
ID: 985370 • Letter: C
Question
Choose one answer for each question:
1.) Increasing the pressure of oxygen above a beaker containing 100 mL of water increases:
a.) the mole fraction of oxygen dissolved in 100 ml water
b.) the number of grams of oxygen dissolved in 100 ml water
c.) the number of moles of oxygen dissolved in 100 ml water
d.) the solubility of oxygen in water
e.) all of the above
2.) A molar fraction of phosphoric acid in an aqueous solution is 0.28. This means that
a.) 1 L of this solution contains 28 mol of phosphoric acid
b.) 1 L of this solution has a 280 mL of phosphoric acid
c.) 100 moles of this solution contain 72 moles of water
d.) 1 L of this solution contains 28 mL of phosphoric acid
e.) the density of this solution is 2.8 g/mL
PLEASE EXPLAIN YOUR ANSWER AND THANK YOU SO MUCH!!!
Explanation / Answer
1. If pressure on a gas increases, the solubility of gas increases in the solution. Therefore, the no. of grams, no. of moles & mole fraction of that in the solution also increases.
So, All of the given options are correct. ANSWER: e
2.A mole fraction of 0.28 for H3PO4 means the mole fraction of water is 0.72
i.e., 1L of solution = 280mL of H3PO4