Mole and Molar Mass

Calculate the mass of 5.22 mol of helium.

Atomic mass of He = 4.003 amu

Don't forget the unit!

Convert 5.62 g of Kr to mol Kr.

1 mol of barium is equal to:

• 6.02 x 10²³ atoms of Barium

• 56 protons

• 137.327 g of barium

• 56 electrons

Tags

NGSS.HS-PS1-1

Determine the mass (in grams) of 1.22 x 10²³ mol Ag.

Tags

NGSS.HS-PS1-1

Calculate the number of atoms in 0.124 g of magnesium.

Don't forget the unit!

The atomic mass of nitrogen is 14.007. That means, in one mole of nitrogen, how many nitrogen atoms do I have?

• 14.007 atoms

• 8.43 x 10²⁴ atoms

• 6.02 x 10²³ atoms

• 1 atom

The atomic mass of argon is 39.948 amu.

Hint: this question is similar to one of the questions in the homework about the gold bracelet.

• 8.44 x 10^19 Ar atoms per breath

• 9.041 x 10^21Ar atoms per breath

• 2.40 x 10^25 Ar atoms per breath

• 4.01 x 10^25 Ar atoms per breath

Answer explanation

9.041 x 10²¹ x .934% = 8.44 x 10¹⁹

Pay attention here! We are given the number of moles of Fe and the grams of Ca.

Atomic mass of calcium is 40.078 amu.

Tags

NGSS.HS-PS1-7