Mole Race

Basics (1)

100

What is the molar mass of a substance? 

Molar mass is the added value of each elements mass in a compound 

200

How any atoms are in one mole?

6.02 x 10²³ atoms 

300

How do you calculate the percent of each element in a compound? 

Find the molar mass of the compound, find the molar mass of each element in grams per mole, divide each element's mass by the total molar mass of the compound, multiply the answer by 100 to get a %

400

What is the molecular formula? 

gives the number of atoms of each element in one molecule of a specific compound 

500

What is the empirical formula? 

The simplest whole integer ratio of atoms in a compound 

Molar mass (2)

100

What is the molar mass of the compound ferrous sulfate? 

FeSO₄= 152 g/mole 

200

What is the molar mass of calcium phosphate? 

Ca₃(PO₄)₂ =310 g/mole 

300

What is the molar mass of sodium acetate? 

NaC₂H₃O₂= 82 g/mole 

400

What is the molar mass of carbon tetrafluoride? 

CF₄= 88 g/mole 

500

What is the molar mass of magnesium chloride heptahydrate? 

MgCl₂ * 7H₂O= 221 g/mole

Conversions (3)

100

Convert from moles to grams: 2.2 moles of silver acetate

2.2 moles AgC₂H₃O₂ x 167 g/mole= 370 grams 

200

Convert from grams to moles of 45.0 grams of ferrous nitride

45.0 grams Fe₃N₂ / 196 g/mole = 0.230 moles 

300

Convert 7.21 moles of nickel chloride hexahydrate to atoms

7.21 moles NiCl₂ * 6H₂O x (6.02 x10²³ )=           4.34 x10²⁴ atoms 

400

Convert 1.30 x 10^-4 atoms of magnesium hydroxide to moles

1.30 x 10^-4 atoms Mg(OH)₂ / 6.02 x 10²³ =        2.16 x 10^-28 moles

500

Convert 1.10 x 10^-5 atoms of phosphoric acid to grams(hint: atoms to moles to grams)

(1.10 x 10^-5 atoms H₃PO₄ / 6.02 x 10²³) x 98 g/mole= 1.79 x 10^-27 grams

Empirical and Molecular Formula (4)

100

Determine the empirical formula: C₆H₄₈O₁₂

CH₈O₂

200

Determine the empirical formula: 15.77% aluminum, 28.11% sulfur, 56.12% oxygen

Al: 15.77 grams / 27 g/mole = 0.584/0.584= 1x2=2

S: 28.11 grams/32 g/mole= 0.878/0.584=1.5x2=3

O: 56.12 grams/16 g/mole= 3.51/0.584=6x2=12

Al₂S₃O₁₂

300

Determine the empirical formula : 53.73% Fe, 46.27% S

Fe: 53.73 g / 56 g/mole= 0.959/0.959=1x2=2

S: 46.27 g / 32g/mole= 1.449/0.959= 1.5x2=3

Fe₂S₃

400

Determine the molecular formula: 94.1% O and 5.9% H Molar mass= 51 g/mole 

O: 94.1g / 16 g/mole= 5.88/5.88=1   

H: 5.9g / 1 g/mole=5.9/5.88=1       

51 g/mole / 17 g/mole= 3 

O₃H₃

500

Determine the molecular formula: 50.7% C, 4.2% H, 45.1% O Molar mass= 213 g/mole

C: 50.7g / 12 g/mole=4.23/2.82=1.5x2=3

H: 4.2g / 1 g/mole= 4.2/2.82=1.5x2=3

O: 45.1g / 16 g/mole=2.82/2.82=1x2=2

213 g/mole / 71 g/mole= 3

C₉H₉O₆

Mixed (5)

100

Find the molar mass of sodium bisulfate 

NaHSO₄= 120 g/mole 

200

Calculate the number of atoms in 7.5 g of Copper (II) acetate (hint: grams to moles to atoms) 

(7.5g Cu(C₂H₃O₂)₂ / 182 g/mole) x 6.02 x 10²³= 2.5 x 10²⁷ atoms

300

Calculate the number of grams in 3.5 x 10^-10 atoms of carbon tetraiodide (hint: atoms to moles to grams)

(3.5 x 10^-10atoms CI₃ / 6.02 x 10²³) x 393 g/mole= 2.3 x 10^-31

400

Who is older Maggie or Maddy? 

Maddy

500

Find the percent of each element in magnesium hydroxide

Mg(OH)₂= 58 g/mole 

Mg: 24/58= .414x100= 41.4%

O: 16g/mole x 2= 32/58= 0.552 x 100= 55.2%

H: 1g/mole x 2= 2/58= 0.034 x 100= 3.4%