The Mole and Molar Mass

How many grams of NH₃ would result in 8 moles of NH_3. What does the the number 8 do to the molar mass of the compound?

• The number 8 is added to the molar mass to give 25 g/mol.

• The number 8 multiplies the molar mass by 8 to give 136 g/mol.

• The number 8 divides the molar mass by 8 to give 2.13 g/mol.

• The number 8 does not change the molar mass of the compound.

A student calculated the number of moles of methane (CH4) present in a 100g sample of a gaseous mixture. If the student determined that there’s 0.6 moles of methane present in the sample, what is the percent composition of methane in the sample?

• .096%

• 9.6%

• .9%

• 90%

The mass of 1 mole is known as

• A mole

• Molar mass

• Percent Composition

• Grams

Tags

NGSS.HS-PS1-7

Given 5 moles of NaCl, which conversion factor would allow you to determine the number of molecules?

• 1 mol = 58 g

• 1 mol = 23 g

• 1 mol = 35 g

• (1x24) + (1x 16) + (2 x 1) = 42 g/mol

• (1x24) + (2x16) + (2x1) = 58 g/mol

• (2x24) + (2x16) + (2x1) = 82 g/mol

• (1x24) + (1x16) + (1x1) = 41 g/mol

Tags

NGSS.HS-PS1-1

What units are used for molar mass?

• mol

• grams (g)

• grams per mole (g/mol)

• Molecules

What is Avogadro's Number?

• 602

• 305

Tags

NGSS.HS-PS1-7

• 1 mol = 84 g

• 1 mol = 18 g

If a dozen = 12, how much does a mole equal?

• 18 g

• 184 g

• 1 mol = 201 g

• 1 mol = 461 g