(46 POINTS) NEED HELP ASAP 1. The chemical equation below shows the combustion of propane (C₃H₈). The molar mass of oxygen gas (O₂) is 32.00 g/mol. The molar mass of C₃H₈ is 44.1 g/mol. What mass of O₂, in grams, is required to completely react with 0.0125 g C₃H₈?

C3H8 +5O2 --> 3CO2 +4H2O

0.091

0.034

0.045

0.018

2. The molar mass of NaOH is 40.00 g/mol. If 308 g NaOH are dissolved in 0.500 L of solution, what is the molarity of the solution?

7.69 M

0.260 M

0.0125 M

15.2 M

3. A sample of sodium bromide (NaBr) has a mass of 412.0 g. The molar mass of NaBr is 102.89 g/mol. Approximately how many moles of NaBr does this sample contain?

160.0

40.00

6,400

4.000

4. The following balanced equation shows the formation of ammonia. How many moles of nitrogen (N2) are needed to completely convert 3.06 mol of hydrogen (H2)? *

N2 + 3H2 --> 2NH3

19.02

2.11

1.02

12.68