Chemistry Unit 7 Solutions & Solubility

This set of flashcards covers key concepts and calculations related to solutions and solubility from Chemistry Unit 7.

How many moles of KOH are contained in 250 mL of a 0.18M solution of NaOH?

0.045 moles of KOH.

What is the formula for calculating percent by mass concentration?

% concentration = (mass part / mass whole) x 100.

What is the percent by mass concentration of a solution where 5.5 g of salt are dissolved in 75.5 g of water?

Percentage by mass = (5.5 g / (5.5 g + 75.5 g)) x 100 = 6.77%.

What is the molarity of a solution of sodium oxalate (NaNO3) containing 45.0 grams of solute in 100.0 mL of solution?

0.45 M.

What is the concentration, in percent by volume, of a solution containing 50.0 mL of diethyl ether in 2.5 L of solution?

2.0% by volume.

What is the solubility of Barium sulfate (BaSO4) at 50°C expressed in parts per million (ppm)?

3.4 ppm.

What is the lead concentration in drinking water that is considered safe?

Below 0.015 ppm.

If a 100 g water sample contains 1.2 x 10^-3 grams of lead, what is the concentration of lead in ppm?

The concentration is 12 ppm.

Is water containing 12 ppm lead considered safe to drink?

No, it exceeds the safe limit.

How many moles of solute are contained in a 4.0M solution of ammonium chloride in 100 mL of solution?

0.4 moles of ammonium chloride.