The ratio of carbon to hydrogen in a hydrocarbon is 1:2. If 7.0g of the hydrocarbon occupies 2.24L at s.t.p, what is its formula?

1 Answer
Mar 24, 2018

# C_5H_10#

Explanation:

2.24 liters = # 1/10 # of a mole.
so one mole has a mass of 70 grams

# 10 xx 7 = 70 #grams

1 formula mass is
# 1 xx C = 1 xx 12 = 12 #
#2 xx H = 2 xx 1 = 2#
# 1 CH_2 = 14 #

# 70/14 = 5 # so there are 5 formula units

# 5 xx CH_2 = C_5H_10#