Answer:
Copper turns green on exposure to air
Explanation:
Liquid water freezes to form ice: Physical change
Reason: Water can melt back when it becomes ice.
Copper turns green on exposure to air: Chemical change
Reason: The copper can not change back from the green state when it turns green.
1. 6 carbon atoms and triple bonding between carbons 2 and 3
2. i think it’s 3 but i may be wrong
The mass of an atom and the equivalent of to the number of protons and neutrons in the atom
Answer:
Energy, 
Explanation:
It is required to find the energy of an electromagnetic wave with a frequency of 
. The energy of a wave in terms of its frequency is given by :
= frequency of em wave
So, the energy of an electromagnetic wave is 
