Percent Composition and Solubility

Front

What is a solute?

Back

A solute is a substance that is dissolved in a solvent to form a solution. For example, sugar is the solute when dissolved in water.

Front

What is the formula for percent composition?

Back

Percent composition = (mass of element in 1 mole of compound / molar mass of compound) x 100%.

Front

What is the molar mass of carbon monoxide (CO)?

Back

The molar mass of CO is approximately 28 g/mol (12 g/mol for C and 16 g/mol for O).

Front

How do you calculate the percent composition of carbon in CO?

Back

Percent composition of carbon in CO = (12 g/mol / 28 g/mol) x 100% = 43%.

Front

What is solubility?

Back

Solubility is the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature.

Front

What is the solubility of NaBr at 70 degrees Celsius?

Back

The solubility of NaBr at 70 degrees Celsius is 120 g per 100 g of water.

Front

What is the molar mass of magnesium bromide (MgBr2)?

Back

The molar mass of MgBr2 is approximately 200.89 g/mol (24.31 g/mol for Mg and 79.9 g/mol for each Br).

Front

How do you calculate the percent composition of magnesium in MgBr2?

Back

Percent composition of magnesium in MgBr2 = (24.31 g/mol / 200.89 g/mol) x 100% = 12.1%.

Front

What is the significance of solubility curves?

Back

Solubility curves graphically represent how the solubility of a substance changes with temperature.

Front

Which substance has the lowest solubility at 30°C: KNO3, KBr, NaCl, or Yb2(SO4)3?

Back

Yb2(SO4)3 has the lowest solubility at 30°C.