Urgent which statement describes a chemical property of hydorgen gas 1. hydrogen gas is colorless 2. hydrogen gas burns in the air 3.hydrogen gas has a density of .00000009 gcm3 4. hydrogen gas has a boiling point of 20k at standard pressure

What sources of error may have contributed to the percent yield not being 100 percent? think about things that may have led to inaccurate measurements or where mass of the product could have been lost if this experiment was conducted in a physical laboratory.