Mole Concept Review

How many Mg ²⁺ ions are found in 1.00 mol of MgO?

• 3.01 x 10 ^23

• 12.04 x 10 ^23

• 6.02 x 10 ^23

• 6.02 x 10 ^25

Tags

NGSS.HS-PS1-7

How many Mg atoms are present in 3.00 moles of MgCl2 ?

• 1.81 x 10^24

• 3.02 x 10^24

• 12.0 x 10^25

• 16.0 x 10^23

Tags

NGSS.HS-PS1-7

Calculate the number of molecules present in 0.20 moles of H₂O.

• 2.9 x 10^25 molecules

• 5.1 x 10^22 molecules

• 1.2 x 10^23 molecules

• 2.4 x 10^23 molecules

The sum of the atomic masses of all the atoms in a formula for a covalent compound is the —

• real mass

• covalent mass

• Avogadro mass

• molecular mass

A molecule has been identified that contains three elements: carbon, hydrogen, and oxygen. When the molecule is broken down, the mass percentages are: C = 40.9% H = 4.58% O = 54.5%

What is the empirical formula for the molecule?

• CHO

• C₃H₄O₃

• CH₂O

• C₁₀HO₁₂

Tags

NGSS.HS-PS1-3

What is the formula mass of sodium chloride, NaCl?

• 53.02 amu

• 58.44 amu

• 102.8 amu

• 112.5 amu

Describe the process of calculating the molar mass of Li₂S.

• Add the masses of 1 mole of lithium and 2 moles of sulfur.

• Add the masses of 1 mole of lithium and 1 mole of sulfur

• Add the masses of 2 moles of lithium and 1 mole of sulfur.

• Add the masses of 2 moles of lithium and 2 moles of sulfur.

How many grams of silicon would there be in a sample that contained 9.99 x 10 ⁵² atoms?

• 1.69 x 10^28

• 4.66 x 10^30

• 1.66 x 10^73

• 1.69 x 10^78

How many moles are there in a sample containing 2.408 x 10 ²⁴ atoms of carbon?

• 2.000

• 4.000

• 6.000

• 12.00

Given three (3.00) moles of gold (Au), how many grams do you have?

• 66 g

• 197 g

• 591 g

• 6.02 x 10^23 g