Question

which of the following is correct concerning subatomic particles?

A) the electron was discovered by Goldstein in 1886.
B) the neutron was discovered by Chadwick in 1932.
C) the proton was discovered by Thomson in 1880.
D) Cathode rays were found to be made of protons.

How many neutrons and protons does a neutral atom of sodium with an atomic mass number of 23 have?

A) 22 neutrons; 11 protons
B) 23 neutrons; 11 protons
C) 11 neutrons; 11 protons
D) 12 neutrons; 11 protons

Answer 1

The following answers:
1. B
2. D

Answer 2

Answer:

1. Option B

2. Option D

Explanation:

Electron was discovered by JJ Thomson when he was studying cathode ray

And neutron was discovered by Chadwick

Proton was discovered by Rutherford

2. No of protons = Atomic number

No of neutrons= A-Z

Atomic number of Sodium=11

Hence no protons=11

No of neutrons=23-11=12