Question

Give reasons for the following:
a. Reaction between hydrogen and
oxygen to form water is a chemical
change.
b. Photosynthesis occurs only during
daytime.​

Answer 1

Answer:

b) Because photosynthesis need sunlight and it is only present during day

Answer 2

Answer:

1 Water can also undergo a chemical change. Water molecules can be broken down into hydrogen and oxygen molecules by a chemical reaction called electrolysis. When an electric current is passed through liquid water (H2O), it changes the water into two gases—hydrogen and oxygen.

2 Plants respire all the time, whether it is dark or light, because their cells need energy to stay alive. But they can only photosynthesize when they have light.

I hope it is helpful for you