1.Hydrogen is colorless odorless gas that is less dense than air it will react with oxygen to form water which of the following is a chemical property of hydrogen?

It is a gas
it is less dense than air
It is colorless
It reacts with oxygen to form water

2. Sodium is a shiny solid at room temperature it will react with chlorine to form table salt it will react violently with water which of the following is a physical property of sodium?

It is a solid at room temperature
it reacts with chlorine to form table salt
it reacts violently with water

3.Mercury has a density of approximately 5.43 g/ml. If a sample of mercury has a volume of 10ml, what must be the mass of the samples

54.3g
5.43g
0.543g
4.57g