Mole Review 1: Avogadro's Number and Molar Mass

How many molecules are in 2.5 mol of NaCl?

• 1.51x10²³
• 146
• 4.15
• 1.51x10²⁴

What is the mass of 0.89 mol of CaCl₂?

• 111 grams
• 0.008 grams
• 98.9 grams
• none of the choices

How many water molecules are in 5.2 moles of water?

• 6.0 x 10²³ molecules

• 5.2 molecules

• 3.1 x 10²⁴ molecules

• 8.6 x 10^-24 molecules

How many moles are in 16.94 g of water? (hint: do you know the formula for water?)

• 16.94 moles

• 0.9403 mole

• 305.2 moles

• 1.063 moles

If you want 1.55 moles of nitrogen trichloride, how many grams should you measure out?

• 0.0129 g

• 120. g

• 187 g

• 9.33 g

What is the definition of molar mass?

• number of grams per one mole of a substance
• whole number ratio that is a multiple of a chemical formula
• simplest, whole number ratio of a chemical formula
• 6.02 x 10^23 particles per one mole of a substance

What is the molar mass of AuCl₃?

• 96 g
• 130 g
• 232.5 g
• 303.3 g

How many moles are present in 32.3 grams of carbon dioxide (CO₂)?

• 44.01 moles
• 1421.52 moles
• 32.3 moles
• 0.73 moles

What is the mass in grams of 5.90 mol C₈H_18?

• .0512 g
• 19.4 g
• 673 g
• 389 g

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

• 40 g
• 80 g
• 16 g
• 32 g