What experiment did j. j thomson do?
a) he suspended charged oil drops in a chamber
b) he shot alpha particles through golf foil
c) he sent a cathode ray between electrically charged metal plates
d) he hit metal plates with light

Option(c)

He sent a cathode ray between electrically charged metal plates

Explanation:

In 1897, physicis JJ Thomson experimented with a device called CRT(cathode ray tube) in which a current passed through gases at a low pressure. A CRT(cathode ray tube) comprises of a sealed glass-duct fitted with electrodes at both ends of the metal disks.

Then the electrodes are connected to an electricity source. One electrode,  known as  anode, will be charged positively while the other electrode, referred as cathode, will be charged negatively. A light beam passes from the cathode to the anode which is called as the cathode ray.

c.

explanation:

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-