Chapter 3: Mole Concept

How many molecules of sugar (C₆H₁₂O₆) are in a mole?

• 24 molecules
• 180 molecules
• 180 g
• 6.02 x 10²³ molecules

How many atoms of carbon are in 6.00 g of carbon?

• 1.20x10²⁴ atoms C

• 6.02x10²³ atoms C

• 3.01x10²³ atoms C

• 1.50x10²³ atoms C

How many grams are in 1.2 x 10²⁴ molecules of CO? (molar mass of CO = 28 g/mol)

• 28.2 g

• 55.8 g

• 6.02 g

• 1.2 g

Tags

NGSS.HS-PS1-7

How many moles are in 3.01 x 10²² atoms of magnesium?

• 0.05 moles

• 1.81 x 10⁴⁶ moles

• 5.00 x 10²¹ moles

• 5 moles

What are the units for molar mass?

• g

• amu

• g mol^-1

• L

How many grams of silicon (atomic mass = 28.1 amu) would there be in a sample that contained 9.99 x 10^22 atoms?

• 1.69 g

• 4.66 g

• 1.66 g

• 1.79 g

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NGSS.HS-PS1-7

What is the definition for Avogadro's number?

• 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

How many grams are in 3.3 mol of Potassium Sulfide? (atomic mass: K = 39.1 g mol^-1; S = 32.1 g mol^-1)

• 364 g

• 454 g

• 238 g

• 132 g

Tags

NGSS.HS-PS1-7

What is the molarity of 4 g of NaCl (M_r NaCl=58.45 g mol^-1) in 3800 mL of solution?

• 0.018 M

• 0.0011 M

• 1.052 M

• 0.062 M

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-7

Find the molarity of 186.55 g of sucrose, C₁₂H₂₂O₁₁ (M_r sucrose = 342 g mol^-1) in 250 mL of water.

• 2.18 M

• 0.746 M

• 2.18 x 10^-3 M

• 746 M