Answer: hydrogen
Explanation: hydrogen gas is a major component of water which occupies a large portion of the Earth's atmosphere
Answer: It is called a Crookes Tube, and he used it to discover cathode rays, which were later determined to be electrons.
Answer:
B
Explanation:
In order for any conduction to take place it needs to go through a solid. Therefore it cannot travel through empty space
Answer: 22g of chlorine would be needed to carry out this synthesis reaction
Explanation:
A synthesis reaction is one in which two or more than two elements combine together to forma single product.

The atoms present in the reactants are found on the product side. According to the law of conservation of mass, the number of atoms on both sides of the arrow must be same as the total mass must be conserved.
15 grams of sodium reacts with 22 grams of chlorine to yield 37 grams of sodium chloride. Thus 22g of chlorine would be needed to carry out this synthesis reaction.