Oxygen was discovered by

Identify the correct statements from the following.
$A$. In photosynthesis reaction,water is oxidized to oxygen.
$B$. An example for interstitial hydride is $MgH_2$.
$C$. Sodium hexametaphosphate is used in the removal of permanent hardness of water.

How is the oxygen atom surrounded in ice?

The velocity of neutrons in a nuclear reactor is slowed down by

Write chemical reactions to show the amphoteric nature of water.

Water does not produce $CO$ on reacting with: