1.2 Atomic structure

Question 1

definition of the atomic number

Answer 1

The atomic number is the number of protons in the nucleus of an atom

Question 2

definition of the mass number

Answer 2

The mass number is the total number of protons and neutrons in the nucleus of an atom.

Question 3

which isotope is known as the standard

Answer 3

carbon-12

Question 4

definition of RMM

Answer 4

The relative molecular mass of a molecule is the average (weighted mean) mass of the molecule relative to one twelth of the mass of an atom of carbon-12

Question 5

definition of RFM

Answer 5

The relative formula mass is the average (weighted mean) mass of a species relative to one twelfth of the mass of an atom of carbon-12

Question 6

what is the definition of an isotope

Answer 6

Isotopes are atoms which have the same number but a different mass number containing the number of protons and electrons but different numbers of neutrons in the nucleus

Question 7

isotopes have the same ? properties but different ? properties

Answer 7

chemical physical

Question 8

what is the definition of RIM

Answer 8

The relative isotopic mass of an isotope is the mass of one atom of the isotope of an element relative to one twelfth of the mass of an atom of carbon 12

Question 9

What is a molecular ion

Answer 9

It is formed by the removal of an ion from a molecule.

Question 10

name given to each shell

Answer 10

principle quantam number

Question 11

what is the formula for number of electrons relative to n

Answer 11

2n^2

Question 12

what is the name of which the electrons occupy within a shell

Answer 12

orbitals

Question 13

what is the definition of an orbital

Answer 13

An orbital is a region of space within an atom that can hold up to 2 electrons with opposite spins

Question 14

Max number of electrons an orbital can hold

Answer 14

2

Question 15

Max number of electrons an s sub-shell can hold

Answer 15

2

Question 16

Max number of electrons a p sub-shell can hold

Answer 16

6

Question 17

Max number of electrons a sub-shell can hold

Answer 17

10

Question 18

rules for filling up subshells

Answer 18

1. Add electrons, one at a time, to build up the atom
2. The lowest available energy level is filled first
3. Each energy level must be full before the next, higher energy level starts to fill
4. When a sub-shell is built up with electrons, each orbital is filled singly before pairing pairs
5. An orbital can hold a maximum of 2 electrons, each with opposite spin

Question 19

eg of orbial kr

Answer 19

1s^2 2s^2 2p^6 5s^2 3p^6 3d^10 4s^2 4p^6

Question 20

what elements are exception

Answer 20

Cr and Cu

Question 21

what is the difference in these elements

Answer 21

last s sub shell only holds one electron

Question 22

what is the definition of an s-block element

Answer 22

An s block element is an element which has an atom with highest energy/outer electron is an s-subshell

Question 23

what is the definition of first ionisation energy

Answer 23

The first ionisation energy is the energy required to convert one mole of gaseous atoms into gaseous ions with a single positive charge

Question 24

first ionisation energy for Na equation example

Answer 24

Na = Na^+ + e^-

Question 25

second ionisation energy definition

Answer 25

The second ionisation energy is the energy required to covert one mole of gaseous ions with a single positive charge into gaseous ions with a double positive charge

Question 26

Definition of third ionisation energy

Answer 26

The third ionisation energy is the energy required to convert one mole of gaseous ions with a double positive charge into gaseous ions with a triple positive.