1.1 Atomic Structure

Question 1

Define aspects of the nucleus

Answer 1

• Tiny + dense
• Contains protons + neutrons (nucleons)
• Contains the majority of the mass of the atom

Question 2

Relative mass + charge

Answer 2

Particle:
Ar:
Cr:

Question 3

Define energy level shells

Answer 3

Electrons orbit around nucleus due to electrostatic forces of attraction between positive nucleus and negative elections

Question 4

Define mass(A)

Answer 4

Number of nucleons in nucleus

Question 5

Define atomic number(z)

Answer 5

Number of protons in nucleus

Question 6

Number of elections

Answer 6

In a stable atom, charges are balanced, therefore, number of protons = number of electrons

Question 7

Define isotope

Answer 7

Atoms with the same number of protons in nucleus, but a different number of neutrons

Question 8

Define relative isotopic mass

Answer 8

Mass of an isotope in comparison relative to one twelfth of the mass of C12

Question 9

How is an atom of Cl38 differently to Cl35 in terms of protons?

Answer 9

Cl37 having two more neutrons than Cl35 have the same number of protons and the same number of electrons

Question 10

How is an atom of Cl37 the same as Cl35 in terms of protons, neutrons and electrons?

Answer 10

Cl37 has same number, but both isotopes have the same number of protons and same number of electrons

Question 11

1803 electron development

Answer 11

Dalton proposed elements composed of atoms
Atoms are invisible and atoms are specific
In different elements there are different atoms
Atoms cannot be broken down

Question 12

1896 electron development

Answer 12

Becquerel discovered radioactivity
Proposing sub-atomic particles
Therefore the atom isn’t visible

Question 13

1897 electron development

Answer 13

Thompson discovered electron via Plum-pudding model

Overwhelmingly positive and dotted with negative with electrons

Question 14

1911 electron development

Answer 14

Rutherford proposed most mass and positive charge in nucleus