Mole-Mass Conversions

Why do we need to be able to convert amounts of chemicals from moles to grams or grams to moles?

• Because we need to use moles when we discuss chemical reactions, but we need to measure in grams

• Because we need to obey the law of Conservation of Mass

• Because we need to use grams when we discuss chemical reactions, but we need to measure in moles

• All of these are true

Which of the following do we use to convert between moles and grams?

• Avagadro's number

• Molar mass

• Atomic number

• None of these

Which of the the following describes how to convert 10.0 g H2O to moles?

• $$10.0g\times \frac{18.015g}{1mol}$$

•  $10.0\ g\ \times\ \frac{1\ g\ }{18.015\ mol}$  

•  $1\ mol\ x\ \frac{18.015\ g}{10.0\ g}$  

•  $10.0\ g\ x\ \frac{1\ mol}{18.015\ g}$  

How many moles are there in 500.0 g of table salt (NaCl)?

• 8.56 mol NaCl

• 0.117 mol NaCl

• 29,222 mol NaCl

• 3.09 mol NaCI

How many grams is 0.750 mol of CuSO₄?

• .004699 g CuSO₄

• 119.7 g CuSO₄

• 212.8 g CuSO₄

• 83.7 g CuSO₄

How many moles is 25.0 g Ag₂CO₃?

• 11.0 mol Ag₂CO₃

• 6,894 mol Ag₂CO₃

• 0.0907 mol Ag₂CO₃

• 0.149 mol Ag₂CO₃

How many grams is 0.117 mol Mg₃(PO₄)₂?

• 30.8 g Mg₃(PO₄)₂

• 27.1 g Mg₃(PO₄)₂

• 23.4 g Mg₃(PO₄)₂

• 42.1 g Mg₃(PO₄)₂