atomic structure

Question 1

Atoms

Answer 1

An atom is the smallest indivisible particle of an element that can take part in a chemical reaction.

Question 2

Protons (charge, relative mass)

Answer 2

Charge: 1+
Relative mass: 1

Question 3

Neutron (charge, relative mass)

Answer 3

Charge: 0
Relative mass: 1

Question 4

Electron (charge, relative mass)

Answer 4

Charge: 1-
Relative mass: 1/1840

Question 5

Behavior of particles in an electric field

Answer 5

Protons: deflected towards the negative plate
Electrons: deflected towards the positive plate
Neutrons: not deflected at all

Question 6

Extent of deflection of protons and electrons

Answer 6

The extent of deflection of electrons towards the positive plate in the electric field will be greater than protons as an electron has a much smaller mass than a proton.

Question 7

Extent of deflection equation

Answer 7

Charge / mass

Question 8

Isotopes (definition)

Answer 8

Isotopes are atoms of the same element with different number of neutrons

Question 9

Isotopes (properties)

Answer 9

Isotopes of the same element have the same chemical properties, because they have the same number of electrons. However, they have slightly different physical properties, due to the different relative masses of isotopes.

Question 10

Atomic orbitals

Answer 10

An orbital is a region of space around the nucleus with the highest probability of locating the electrons

Question 11

s orbitals

Answer 11

All s orbitals are spherical in shape, they only differ in size

Question 12

p orbitals

Answer 12

There are 3 types of p orbitals (px,py,pz) with different orientations in space. Each p orbital has a dumb-bell shape

Question 13

Four types of orbitals

Answer 13

s, p, d, f

Question 14

Maximum number of electrons that can occupy each shell

Answer 14

2n 2

Question 15

Maximum number of electrons each orbital can hold

Answer 15

2

Question 16

Subshell s

Answer 16

1 orbital, maximum of 2 electrons

Question 17

Subshell p

Answer 17

3 orbitals, maximum 6 electrons

Question 18

Subshell d

Answer 18

5 orbitals, maximum 10 electrons

Question 19

Subshell f

Answer 19

7 orbitals, maximum 14 electrons

Question 20

Electron shell 1

Answer 20

1 subshell (1s), maximum 2 electrons

Question 21

Electron shell 2

Answer 21

2 subshell (2s, 2p), maximum 8 electrons

Question 22

Electron shell 3

Answer 22

3 subshell (3s, 3p, 3d), maximum 18 electrons

Question 23

Electron shell 4

Answer 23

4 subshell (4s, 4p, 4d, 4f), maximum 32 electrons

Question 24

4s vs 3d subshells

Answer 24

The orbitals are always filled in the order of increasing energy. Electrons always go into an empty orbital with the lowest energy first.
4s has a lower energy level than 3d. Thus, when adding electrons, the 4s orbital is filled up before the 3d orbital.

Question 25

Ions (definition)

Answer 25

An ion is formed when an atom loses or gains electron(s), such that it acquires an electrical charge. Atoms lost or gain electrons to obtain the duplet or octet configuration in order to achieve greater stability

Question 26

Formation of ions (anion)

Answer 26

When atoms gain elections, negative ions are formed (anions). Electrons are first added into available orbitals with the lowest energy.

Question 27

Formation of ions (cations)

Answer 27

When atoms lose electrons, positive ions are formed (cations). Electrons are first removed from orbitals with the highest energy. When the 3d orbital is filled, the energy level of the 4s orbital will increase above that of the 3d orbital. Thus, during the formation of cations, the electrons will be removed from the 4s orbital before the 3d orbital.

Question 28

Isoelectric species

Answer 28

Any atom or ions with same number of electrons are said to be isoelectronic.