Solutions and Solubility

Which change will most quickly increase the rate of solvation for a solid solute in water?

• Cooling the solvent to a lower temperature

• Leaving the mixture completely undisturbed

• Using a solute with a larger particle size

• Crushing the solute into smaller pieces

As temperature increases, how does the solubility of a gas in water generally change?

• It decreases for most gases

• It stays exactly the same

• It first increases then always decreases

• It increases for most gases

Match each colligative property change with the direction it shifts when a nonvolatile solute is added to a solvent.

• Decreases

• Freezing point

• Decreases

• Boiling point

• Increases

• Vapor pressure

A solution is made by dissolving 1.9 moles of C6H12O6 in enough water to make 2.5 L of solution. What is the molarity of the solution?

• 1.3 M

• 2.4 M

• 0.76 M

• 0.19 M

Tags

NGSS.HS-PS1-5

Give the mole ratios below for the following reaction: 2 KClO3 → 2 KCl + 3 O2. a. O2:KClO3 ____________ b. KCl:O2 ____________

• 3:2 and 2:3

• 2:3 and 3:2

• 1:2 and 2:1

• 3:1 and 1:3

Tags

NGSS.HS-PS1-7

For the reaction 3 Li + AuCl3 → 3 LiCl + Au, how many moles of lithium chloride (LiCl) can be produced from 7.5 moles of gold (Au)?

• 2.5 moles LiCl

• 7.5 moles LiCl

• 3.0 moles LiCl

• 22.5 moles LiCl

For the reaction 3 Li + AuCl3 → 3 LiCl + Au, how many grams of gold (Au) can be produced from 4.75 moles of lithium (Li)? (Molar masses: Li ≈ 6.94 g/mol, Au ≈ 197.0 g/mol)

• 312 g Au

• 93 g Au

• 450 g Au

• 197 g Au

Tags

NGSS.HS-PS1-7

A student calculated the amount of product to be produced as 264 g. The lab produced 272 g. What is the percent yield?

• 88.0%

• 96.9%

• 100.0%

• 103.0%

Tags

NGSS.HS-PS1-7

Which statement best defines a mole in chemistry?

• A fixed mass equal to 1.00 gram of atoms

• A fixed charge equal to one coulomb of ions

• A fixed volume equal to 22.4 liters at STP

Avogadro’s number is used to convert between which two quantities?

• Atoms and meters for any element

• Moles and grams for any compound

• Grams and liters for any gas

• Particles and moles for any substance