Chapter 2:The Atom

Question 1

Dalton’s Atomic Theory

Answer 1

All matter is made up smal partices called atom’

Alow are indivisible.they can be broken down into simplier particles.

Question 2

Who discovered Cathode Rays?

Answer 2

William Crookes

Question 3

Cathodes Rays

Answer 3

Travels in straight lines from the cathode to the anodes,are deflected by electric and magnetic fields
Causes glass to fluorese
Posesses enough energy to move a paddle wheel
They are streams of negatively charged particles called electrons.

Question 4

Who named the electron?

Answer 4

George Stoney

Question 5

Who discovers the proton?

Answer 5

Ernest Rutherford

Question 6

How did Robert Millikan measure the charge of an electron?

Answer 6

1. Used x-rays to ionise the air between the plates
2. Oil droplets fell through the air they picked up these electrons.
3. Using a microscope,Milkan focused on an oil droplet As it fell through the air.
4. Places the positively charge on the top plate and observed the negatively charged oil droplet was attracted towards the positive plate.
5. He carefully adjusted the charge on the plate until the oil droplet was completely stationary.

Question 7

What did Thomson do?

Answer 7

He tried the cathode ray experiment again with a large electromagnet
1.He placed it outside the glass tube & adjusted the strength at the magnetic field

2.He found that the electrons were deflected in the magneticy.Using the beam he was able to bring the beam at electrons back down to it’s original position