ERHS Chem Unit 11 - The Mole

What is Avogadro's Number for the chemical NaCl?

• 6.02 x 10²³

• 58.44

• 3.51 x 10²⁵

• 1.03 x 10²²

How are the mole and atomic masses of elements related?

• The atomic mass of any substance is always equal to 1 mole of that substance

• The atomic mass states that one gram of any substance contains 6.02 x 10²³ particles of the substance.

• The atomic mass is always 6.02 x 10²³ grams of a substance.

• Atoms combined make up molecules, which are the measurement of atomic masses

Which compound has the smallest molar mass?

• CO
• CO₂
• H₂O
• H₂O₂

What is the mass of 2.50 mol of oxygen gas O₂?

• 40.0 g
• 80.0 g
• 16.0 g
• 32.0 g

What is the molar mass of lead (II) nitrate?

• 476.41 g/mol

• 283.32 g/mol

• 269.22 g/mol

• 331.22 g/mol

How many atoms are in 0.500 mole of aluminum?

• 13.49 atoms

• 6.02 x 10²³ atoms

• 3.01 x 10²³ atoms

• 1.21 x 10²⁴ atoms

How many moles is 397 g of calcium chloride (CaCl₂)?

• 111 moles

• 3.58 moles

• 0.280 moles

• 44100 moles

If you burned 6.10 x 10²⁴ molecules of ethane (C₂H₆), what mass of ethane did you burn?

• 304 g

• 1.22 x 10⁴⁷ g

• 10.1 g

• 30.1 g

If I have 678 g of CO₂, how many molecules is it?

• 4.08 x 10²⁶ molecules

• 15.4 molecules

• 9.27 x 10²⁴ molecules

• 1.80 x 10²⁸ molecules

How many moles are in 16.94 g of water?

• 16.94 mol H₂O
• 0.9401 mol H₂O
• 305.3 mol H₂O
• 1.063 mol H₂O