What element glows in sign's when excited

neon

Explanation:

The gas is placed in glass tubes and an electric current is sent through the gas. When excited, neon enters a plasma state and glows red. Neon is the tenth element of the periodic table and the second of the noble gases.

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.