C1.5History Of The Atom

Question 1

Who were the first people to come up with the idea that everything could be broken down into something(atom)?

Answer 1

Ancient greeks

Question 2

What did john Dalton discover?

Answer 2

He discovered atoms were in spheres.

Question 3

When did John Palton discover this?

Answer 3

1800

Question 4

Who discovered in 1800 atoms were in spheres?

Answer 4

John dalton

Question 5

What did JJ Thomson come up with

Answer 5

The plum pudding model

Question 6

When did JJ Thompson create the Plum pudding model?

Answer 6

1897

Question 7

Who created the plum pudding model?

Answer 7

JJ Thompson

Question 8

When did Ernest Rutherford do his experiment

Answer 8

1909

Question 9

What did Rutherford discover?

Answer 9

1. Mass concentrated in the centre
2. Most of the mass in the nucleus
3. Most of the atom is empty space
4. The nucleus is charged
5. Plum pudding model disproven

Question 10

Who proved the plum pudding model wrong?

Answer 10

Rutherford

Question 11

What was the plum pudding?

Answer 11

A model that said negatively and positively charged atoms are everywhere in random places like fruit in a plum pudding.

Question 12

Niels bohr date of discovery?

Answer 12

1913/1914 kerboodle and google say different things.

Question 13

What did Bohr discover?

Answer 13

Electrons are in shells at set distances orbiting the nucleus.

Question 14

Who discovered Electrons are in shells orbiting the nucleus?

Answer 14

Niels Bohr

Question 15

When was James Chadwick’s discovery?

Answer 15

1932

Question 16

What did James Chadwick discover?

Answer 16

Discovered neutrons

Question 17

Who Discovered neutrons?

Answer 17

James Chadwick

Question 18

What did Dalton suggest?

Answer 18

He suggested substances were made up of atoms like tiny hard spheres.

2: He also suggested that each chemical element had its own atoms that differed from others in their mass.
3: He also believed they could not be divided or split.

Question 19

Who discovered the electron?

Answer 19

J.J Thomson

Question 20

When was the electron discovered?

Answer 20

1897

Question 21

What was discovered about the electron?

Answer 21

It has 1/2000 the mass of the lightest atom CHECK I AM NOT SURE.

Question 22

How was the electron discovered?

Answer 22

Thomson’s experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons

Question 23

Describe the experiment J.J Thomson did that discovered the electron.

Answer 23

Gas at very low pressure in a cylinder, a thin slit at the end glass glows through slit by rays coming from negative electrode(the streams of negative electrons.

Question 24

What is the name pf the experiment that discovered the electron?

Answer 24

Cathode ray tube

Question 25

Why did J.J Thompson come up with the plum pudding model?

Answer 25

He knew that atoms themselves were neutral so any charges must balance out. He imagined the electrons as bits of a plum pudding.

Question 26

What is the name of the experiment carried our by Geiger and Marsden students?

Answer 26

The alpha particle scattering experiment.

Question 27

What is Rutherford’s model of the atom called?

Answer 27

The nuclear model.

Question 28

Describe the alpha scattering experiment.

Answer 28

Firing dense positively charged particles called alpha particles at the thinnest piece of gold foil they could make. They expected the particles to pass straight through the gold atoms with their defused cloud of positive charge(J.J Thompson theory). The positively charged particles must be in a tiny sport in the centre due to the large positive particles being fired being repelled back to the source. Therefore it was preposed electrons must orbit around the nucleus which contains dense and positively charged protons.

Question 29

What did Niels Bohr notice?

Answer 29

The light given out when atoms were heated only had a specific amount of energy,he suggested electrons must be in shells and orbit at set distances because the energy given out must have been given out when exited electrons fall from a high to a low energy level (shell to shell) Bohr made a model for this.

Question 30

How did scientists know there was something els something els in the atom before James Chadwick’s discovery?

Answer 30

There was missing mass that had been noticed in the atom. Scientists speculated there were two types of sub-atomic particles in the nucleus.