L1 Particles And Radiation- Constituents Of An Atom (Overview)

Question 0

How big is an atom?

Answer 0

Less than a millionth of a mm in diameter.

Question 1

What is the diameter of the nucleus of an atom?

Answer 1

0.00001 times the diameter of an atom.

Question 2

Describe how Rutherford’s alpha scattering experiment in 1909 was carried out.

Answer 2

Fired beam of alpha particles at thin gold foil.

Question 3

What was the expected result of Rutherford’s alpha scattering experiment in 1909?

Answer 3

Expected positively charged alpha particles to be deflected by electrons in plum pudding model.

Question 4

What was the actual (and rather surprising at the time) result of Rutherford’s alpha scattering experiment in 1909?

Answer 4

Most of the alpha particles went straight through, but the odd one was deflected.

Question 5

What 4 conclusions regarding the atom came up thanks to the results of Rutherford’s alpha scattering experiment in 1909?

Answer 5

1. Most mass of atom concentrated at centre in tiny nucleus.
2. Nucleus= positively charged (repelled positive alpha particles) + composed of protons and neutrons.
3. Electrons surround the nucleus.
4. Most of an atom is just empty space.

Question 6

What force of attraction between the nucleus and the electrons holds the electrons in the atom?

Answer 6

The electrostatic force of attraction.

Question 7

The electron has a much smaller mass than what 2 other constituents of the atom?

Answer 7

The proton and neutron.

Question 8

The proton and neutron have almost equal……

Answer 8

Mass.

Question 9

Which constituent of the atom has equal and opposite charge to the proton?

Answer 9

The electron.

Question 10

The neutron is known for being…..

Answer 10

Uncharged.

Question 11

In isotope notation which letter stands for the nucleon number/mass number and where is this letter positioned.

Answer 11

A. Top left.

Question 12

In isotope notation which letter stands for the Chemical symbol and where is it positioned?

Answer 12

X. Middle.

Question 13

In isotope notation which letter stands for the Atomic number and where is it positioned?

Answer 13

Z. Bottom left.

Question 14

Every atom of a given element has the……..as any other atom of the same element.

Answer 14

Same number of protons.

Question 15

What name is given to the form of an element that has the same number of protons but a different number of neutrons?

Answer 15

Isotope

Question 16

Isotopes have the same………properties as their element.

Answer 16

Physical and Chemical.

Question 17

What is another phrase for mass number?

Answer 17

Nucleon number

Question 18

Some isotopes are……., as the……..are unstable.

Answer 18

Radioactive. Nuclei.

Question 19

Why is the nucleon number the same as the mass number?

Answer 19

Because it’s numerically equal to the mass of the atom in relative units (where mass of a proton/neutron is approximately 1).

Question 20

What 2 constituents of an atom could a nucleon be?

Answer 20

A proton/neutron.

Question 21

What is another word for each type of nucleus that is labelled using isotope notation?

Answer 21

Nuclide.

Question 22

Which constituent of an atom has the largest specific charge?

Answer 22

The electron.

Question 23

The……of a particle is defined as its charge divided by its mass.

Answer 23

Specific charge.