Q5) Consider the combustion reaction between 13 ethane molecules and 42 oxygen molecules. Identify the limiting reactant. (Chapter 3)
A) water
B) ethane
C) none of the above
D )carbon dioxide
E) oxygen

Q7) Determine the molarity of a calcium hydroxide (molar mass: 74.10 g/mol) solution if 34.53 mL of the calcium hydroxide solution is required to neutralize 15.41 mL of a 2.456 M hydrochloric acid (molar mass: 36.46 g/mol) solution.
A)1.096 M
B)none of the above
C)5.480 × 10-4 M
D)0.5480 M
E)1.096 × 10-3 M

Q9) In which of the following orbitals does an electron in a rubidium atom experience the least effective nuclear charge?
A)2p
B)5s
C)7s
D)4d
E)3s

Q10) Using Lewis structures, determine the number of sigma (σ) and pi (π) bonds are there in a carbon dioxide molecule?
A) 1 σ and 2 π bonds
B) 2 σ and 2 π bonds
C) 3 σ bonds
D) 1 σ and 1 π bonds
E) none of the above

Q12) Using the Lewis structures for a carbon dioxide molecule and a carbonate ion, which of the following statements is true?
A) A carbonate ion has two different carbon-oxygen bond lengths, where one of the carbon-oxygen bonds is the same length as the carbon-oxygen bond in a carbon dioxide molecule.
B) A carbon dioxide molecule has two carbon-oxygen bond lengths, where one of the carbon-oxygen bonds is the same length as the carbon-oxygen bond in a carbonate ion.
C) none of the above predictions are true
D) All of carbon-oxygen bonds in a carbonate ion are shorter than the carbon-oxygen bonds in a carbon dioxide molecule.
E) All of the carbon-oxygen bonds in a carbonate ion are weaker than the carbon-oxygen bonds in a carbon dioxide molecule.

Q19) Calculate the number of grams of sodium hydroxide (molar mass: 40.00 g/mol) required to make 50.0 mL of a 0.200 M solution.
A) 0.400 g
B) 0.0100 g
C) none of the above
D) 4.00 x 102 g
E) 10.0 g