1. Identify the reactants and the products in the following equation. (1 point)

CaO + CO2 → CaCO3
2. Show the molecular formula and electron structure of the simplest compound that forms with only carbon and hydrogen atoms. (1 point)
3. For each equation, state the reaction type and then balance the equation. (2 points)
a. ___Na3PO4 + ___HCl → ___H3PO4 + ___NaCl
b. ___KClO3 → ___KCl + ___O2
4. You have knowledge of the outermost electron states of the atoms, trends in the periodic table, and the patterns of chemical properties. Use that knowledge to predict the products of each of the following equations. Then explain how you made your predictions. Be sure to balance the equations. (4 points)
a. ___NaBr + ___Ca → _______ + _______
b. ___Mg + ___O2 → _______
5. Identify the products of this single-replacement reaction between sulfuric acid and aluminum. Then balance the equation. (2 points)

___H2SO4 + ___Al → ___ + ___
6. (6 points)
a. Write a balanced equation for the model of a chemical reaction shown below. (The white balls represent hydrogen atoms, the black balls represent carbon atoms, and the gray balls represent oxygen atoms.) Then complete the table with information about the atoms and molecules represented in the model. Show your work. (5 points)
chemical equation
Molecule name Methane Oxygen Water Carbon dioxide
Molecular formula
H2O
Elements in molecule
C, O
Molecular mass of molecule 16.05 g/mol
Total mass in reaction
64.00 g
Total mass of all reactant molecules
Total number of reactant atoms
Total mass of product molecules
Total number of product atoms
b. How does your second table support the claim that the number of atoms — and therefore mass — is conserved during a chemical reaction? (1 point)
7. (6 points)
a. Calculate the molar mass of sucrose: C12H22O11. Show your work. (2 points)
b. Calculate the molar mass of glucose, one of the products of photosynthesis: C6H12O6. Show your work. (2 points)
c. How many molecules are in 1 mole of sucrose? (1 point)
d. How many atoms are in 1 mole of sucrose? (1 point)
8. Baking soda (NaHCO3) and vinegar (HC2H3O2) react to form sodium acetate, water, and carbon dioxide. If 42.00 g of baking soda react, how many moles of carbon dioxide will form? Show your work. (3 points)
NaHCO3 + HC2H3O2 → NaC2H3O2 + H2O + CO2