Quizizz: Chemistry and Math Review

Quizizz: Chemistry and Math Review

Formula Mass

Calculate the mass of a formula by adding the masses of all atoms in the formula. The mass of each atom can be found in the upper left corner of each box on the Periodic Table.

Multiple Choice

What is the mass of one Neon atom?

• 10 amu

• 10 grams

• 20 amu

• 20 grams

Multiple Choice

What is the mass of one molecule of CCl₄?

• 152 grams

• 152 amu

• 47 amu

• 82 amu

Gram Formula Mass

The formula mass in grams is equal to the mass of one mole (6.02 x 10²³) of the substance.

Multiple Choice

What is the mass of one mole of Neon atoms?

• 10 amu

• 10 grams

• 20 amu

• 20 grams

Multiple Choice

What is the mass of one mole of CCl₄ molecules?

• 152 grams

• 152 amu

• 47 amu

• 82 amu

Percent Composition

See the formula/equation for calculating percent composition on Reference Table T!

Multiple Choice

What is the percent by mass of fluorine in CaF₂ (gram-formula mass = 78 g/mol)?

• 24%
• 49%
• 51%
• 65%

Multiple Choice

What is the percent by mass of magnesium in MgO?

• 20%
• 40%
• 50%
• 60%

Hydrates

Hydrates are ionic compounds that contain water molecules. You must be able to calculate the percent water in a hydrate when given the chemical formula of the hydrate and experimental data.

Multiple Choice

Calculate the % water in the hydrate MgSO₄*7H₂O.

• 48.8%

• 99.9%

• 51.2%

• 0.1%

Multiple Choice

A 4.175 gram sample of a certain hydrate of copper (II) sulfate, is heated until all the water is driven off. The resulting anhydrous compound has a mass of 3.120 grams. What is the % water in the hydrate? 

• 74.73%

• 25.27%

• 99.99%

• 0.11%

Multiple Choice

A hydrate of magnesium chloride is present and the following data is collected:

mass of crucible = 22.130 grams

mass of crucible + hydrate = 25.290 grams

mass of crucible and contents after heating = 23.491 grams

What is the % composition of water in this hydrate?

• 56.93%

• 43.07%

• 50.00%

• 25.75%

The Mole Concept

1 mole = 6.02 x 10²³

Molar mass = the mass of one mole of a substance (the gram formula mass)

Mole Conversions

Use the mole calculations equation on Reference Table T to convert grams to moles and moles to grams!

Multiple Choice

How many molecules of sugar (C₆H₁₂O₆) are in one mole?

• 24 molecules

• 180 molecules

• 180 g

• 6.02 x 10²³ molecules

Multiple Choice

What is the molar mass of table salt (NaCl)?

• 116.886 g/mol
• 35.453 g/mol
• 22.990 g/mol
• 58.443 g/mol

Multiple Choice

How many moles of sodium chloride are in a 321.8 g sample?

• 18810 moles

• 3.315 x 10²⁴ moles

• 5.507 moles

• 4.767 moles

Multiple Choice

What is the mass of 0.89 mol of CaCl₂?

• 111 grams

• 0.008 grams

• 98.9 grams

• none of the choices

Multiple Choice

How many moles are in 98.3 grams of aluminum hydroxide, Al(OH)₃?

• 1.26 moles

• 0.8 moles

• 7,670 moles

• 1.63 x 10^-22 moles

Multiple Choice

Determine the mass of 4.20 moles of C₆H_12.

• 353 g

• 0.0499 g

• 337 g

• 2.53 x 10²⁴ g

Counting Atoms

The coefficients (big numbers) and subscripts (little numbers) in chemical formulas now indicate moles of particles!

Multiple Choice

How many moles of Oxygen atoms are in Al₂(SO₄)₃?

• 4

• 12

• 7

• 24

Multiple Choice

How many moles of atoms are there TOTAL in:

H₂SO₄

• 6

• 5

• 7

• 3

Multiple Choice

How many moles of Magnesium atoms are in 10MgCl₂?

• 10

• 5

• 20

Multiple Choice

How many moles of Oxygen atoms are in H₂O?

• 1

• 2

• 0

• 4

Multiple Choice

How many moles of Hydrogen atoms are in 4H₂O?

• 6

• 8

• 2

• 4

Molecular and Empirical Formulas

The molecular formula indicates the actual number of moles of atoms present in a compound, while the empirical formula is the reduced form.

Multiple Choice

What is the best definition for coefficient?
 

• The big number that tells you the number of molecules.
• The little number that tells the number of atoms for each element.
• The atomic number

Multiple Choice

A formula with the lowest whole # ratio of elements in a compound is called

• Molecular Formula
• Chemical Formula
• Empirical Formula 
• Distance Formula

Multiple Choice

What is the empirical formula for C₄H₆?

• CH

• CH₃

• C₂H₃

• C₄H₆

Multiple Choice

What is the empirical formula for N₂S₃?

• NS

• N₃S₂

• N₂S₃

• N₁S_1.5

Multiple Choice

Which pair has the same empirical formula?

• NaCrO₄ and Na₂Cr₂O₇
• C₂H₄O₂ and C₆H₁₂O₆
• C₃H₆O₃ and C₂H₆O₂
• CH₄ and C₂H₆