What test was used to identify hydrogen gas? Write a balanced equation to represent the test?

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

What is the effect of returning nuclear reactor cooling water back into bodies of water?

Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.