Moles, Mass, and Avogadro's Number

How many molecules are in 2.5 mol of NaCl?

• 1.51x10²³
• 146
• 4.15
• 1.51x10²⁴

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

• 1.20x10²⁴atoms C
• 6.02x10²³atoms C
• 3.01x10²³atoms C
• 1.50x10²³atoms C

Tags

NGSS.HS-PS1-7

What are the units for molar mass?

• grams
• amu
• grams/mole
• liters

What is the mass of 0.89 mol of CaCl₂?

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

Avogadro’s number is:

• 6.02 x 10²²

• 6

• 6.02 x 10²³

• 3.01 x 10²³

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

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

How does one get the mass of one mole of any element?

• Look up the average atomic mass from the periodic table

• Look up the atomic number from the periodic table

• Look up the number of neutrons of an atom

• Count Avogadro's Number of atoms and then put them on a balance

What is the mass of 2.589 x 10²² atoms of uranium. Average atomic mass of U is 238.0289 amu.

• 10.23 g

• 0.04299 g

• 0.09769 g

• 238.0289 g

To change mass to atoms, how many conversion factors would need to be used?

• 2

• 3

• 1

• 5

Tags

NGSS.HS-PS1-7