Name That Compound
What’s the name of Na₂O?
Sodium oxide
This compound has the formula HNO₃.
What is nitric acid?
What is Avogadro’s number?
6.022 × 10²³ particles/mol
What is the molar mass of H₂O?
18.02 g/mol
Convert 2.00 moles of CO₂ to grams.
88.02 g
(2 mol × 44.01 g/mol)
What is the formula for molarity?
M = mol/L
Name the compound Cu₂O.
Copper(I) oxide
(Because copper has a +1 charge in this compound to balance O’s -2 charge.)
This ionic compound is made of calcium and carbonate (Ca²⁺ and CO₃²⁻).
What is calcium carbonate?
How many particles are in 3.00 moles of any substance?
1.81 × 10²⁴ particles
Find the molar mass of NaCl.
58.44 g/mol
Convert 90.0 grams of H₂O to moles.
5.00 mol
(90.0 g ÷ 18.02 g/mol)
What is the molarity of a solution made by dissolving 5.00 moles of solute in 2.00 L of solution?
2.50 M
(5.00 mol ÷ 2.00 L)
What is the difference between naming ionic and covalent compounds?
Ionic compounds use charges to determine names (often with Roman numerals); covalent compounds use prefixes like mono-, di-, tri- to show the number of atoms.
The formula Na₂SO₄ represents this compound.
What is sodium sulfate?
You have 1.505 × 10²⁴ molecules of H₂O. How many moles is that?
2.50 moles
Calculate the molar mass of C₆H₁₂O₆.
180.16 g/mol
How many molecules are in 44 g of CO₂?
6.02 × 10²³ molecules
(44 g ÷ 44.01 g/mol = 1 mol → 1 mol × 6.022 × 10²³)
How many moles are in 500.0 mL of a 1.50 M NaCl solution?
0.750 mol
(0.500 L × 1.50 M)
Name Fe(NO₃)₃ using Roman numerals.
Iron(III) nitrate
This acid has the formula H₂SO₃.
What is sulfurous acid?
Why is Avogadro’s number important in chemistry?
It allows you to count atoms/molecules using mass and moles in the lab.
Define molar mass and describe how it’s used in conversions.
Molar mass is the mass of one mole of a substance. It's used to convert between grams and moles.
What type of conversion would require using both molar mass and Avogadro’s number?
When converting from grams to particles (or vice versa), both molar mass and Avogadro’s number are needed.
How many grams of NaOH are needed to make 250 mL of a 0.200 M solution?
2.00 g
(0.250 L × 0.200 mol/L = 0.050 mol → 0.050 × 40.00 g/mol)
Write the name for PCl₅ and explain how you know it’s covalent.
Phosphorus pentachloride; it’s covalent because both phosphorus and chlorine are nonmetals, so prefixes are used.
This compound contains ammonium and phosphate ions. Its formula is (NH₄)₃PO₄.
What is ammonium phosphate?
How many atoms are in 2.00 moles of oxygen gas (O₂)?
2.41 × 10²⁴ atoms
(O₂ has 2 atoms per molecule, so: 2.00 mol × 6.022 × 10²³ × 2 = 2.41 × 10²⁴ atoms)
What is the mass of 2.5 moles of calcium carbonate (CaCO₃)?
250.25 g
(Molar mass of CaCO₃ = 100.09 g/mol → 2.5 mol × 100.09 = 250.23 g)
You have 1.00 × 10²³ molecules of NH₃. How many grams is this?
2.83 g
(1.00 × 10²³ ÷ 6.022 × 10²³ = 0.166 mol → 0.166 × 17.03 g/mol = 2.83 g)
You have 0.20 moles of NaCl dissolved in 250 mL of solution. What is the molarity?
0.80 M
(0.20 mol ÷ 0.250 L = 0.80 M)