Unit 7 Mole Concept

Calculating with SF

100

When adding and subtracting, the fewest  _________ should be used for rounding the final answer.

Decimal Places

200

Provided the final answer to the correct precision according to our sig fig rules.

54.00 ft + 3.5 ft =

57.5 ft

300

Provided the final answer to the correct precision according to our sig fig rules.

4.00 cm x 5 cm=

20cm²

400

Provided the final answer to the correct precision according to our sig fig rules.

1925 ft - 1.225 ft =

1924 ft

500

Provided the final answer to the correct precision according to our sig fig rules.

3.4 x 10³² kg ÷ 1.6 x 10⁴⁵ m³=

2.1 x 10^-13 kg/m³

600

Provided the final answer to the correct precision according to our sig fig rules.

12.5 moles x 122.10 g/moles =

1530 g

Molarity

100

What is the substance that gets dissolved called?

Solute

200

What is the substance that does the dissolving called?

Solvent

300

What is the equation for Molarity?

Molarity = Moles of Solute / Liters of Solution

400

Determine the Molarity of a solution containing 1.50 mols of CaCl₂ in 3.00L of solution.

0.500M

500

Determine the molarity of a solution containing 0.250 moles of calcium chloride in 0.750 L of solution.

0.333M

600

Determine the Molarity of a Solution containing 5.0 moles of BaCl₂ in 1.33L of solution?

3.8M

Molar Mass

100

What is the molar mass of Helium (He)?

4.003 g/mol

200

True or False: 1 mole of Helium has the same number of atoms as 1 mole of Nitrogen.

True

300

True or False: 1 mole of potassium (K) has a different mass than 1 mole of copper (Cu).

True

400

Calculate the molar mass of (NH₄)₂CO₃.

96.094 g/mol

500

Calculate the molar mass of Cr₂(SO₄)₃.

392.21 g/mol

600

6.02 x 10²³ atoms of calcium would have what mass?

40.08 g

Mole Conversions

100

When you are given moles and asked to solve for mass, what must you do?

Multiply the given by the molar mass

200

When you are given mass and asked to solve for moles, what must you do?

Divide the given by the molar mass

300

How many moles are in 95 g of KCl?

Molar Mass of KCl = 74.55 g/mol

1.3 Moles

400

How many grams are in 1.5 moles of AgCl?

Molar Mass of AgCl = 143.32 g/mol

210 g

500

How many moles are in 128 g of NaCl?

Hint: Solve this first!!! Molar Mass of NaCl = _______  g/mol

2.19 moles

600

How many grams are in 2.35 moles of Mg(NO₃)₂?

Hint: Solve this first!!! Molar Mass of Mg(NO₃)₂ = _______  g/mol

349 g