Ratio of hydrogen to oxygen in water is:

A

2:1

B

1:2

C

7:1

D

8:1

The ratio of hydrogen to oxygen in water is 2:1.
Two molecules of the diatomic hydrogen gas, combine with one molecule of the diatomic oxygen gas to produce two molecules of water. In other words the ratio of hydrogen to oxygen is 2:1, the ratio of hydrogen to water is 1:1, and the ratio of oxygen to water is 1:2.
2H2​+O2​→2H2​O