CHAPTER 2 - ATOMS, IONS, AND COMPOUNDS

Question 1

What is an atom comprised of?

Answer 1

Proton, Neutron, Electron

Question 2

What is the relative masses of protons, neutrons and electrons?

Answer 2

P: 1

N:1

E: 0.0005 or 1/1836th of a proton

Question 3

What are the charges of a proton, neutron and electron?

Answer 3

P: +

N: No charge

E: -

Question 4

How many elements are there on the periodic table?

Answer 4

114 (as of 2014)
118 (as of 2018)

Question 5

What is an isotope?

Answer 5

Atoms of the same element wit different numbers of neutrons and different masses (Same Protons and electrons)

Question 6

Mass Number =….?

Answer 6

Number of protons+number of neutrons

Question 8

Atomic number (Proton number) =…?

Answer 8

Number of protons

Question 9

Does the varying number of neutrons in an isotope change its chemical reactivity?

Answer 9

No as there are the same amount of electrons and Neutrons have no effect on a reaction of an element

Question 10

What is a difference that can be seen through isotopes of an element?

Answer 10

Higher mass of an element

Higher melting point/BP

Higher density

Question 11

What does heavy water do?

Answer 11

Controls processes in Nuclear reactors

Question 12

How is Heavy water different to normal water?

Answer 12

Hydrogen atoms contain a Neutron

Relative mass of 2

Question 13

What is Heavy water also known as?

Answer 13

Deuterium (D)

Question 14

What is another isotope of water and how is it different from water and deuterium?

Answer 14

Tritium (T) and it contains 2 neutrons per hydrogen atom (relative mass of 3)

Question 15

What is the relative mass of a molecule of
H2O
D2O
T2O

Answer 15

18
20
22

Question 16

Predict how the melting point, boiling point and density of T2O would be different from H2O and D2O

Answer 16

Melting point would be higher, density would be greater

Question 17

What is a Cation?

Answer 17

A positive ion (Positive to iron a cat)

More protons than electrons

Question 18

What is an Anion?

Answer 18

Negative ion

More electrons than protons

Question 19

State the number of protons, neutrons and electrons in the following isotopes
12 6C
13 6C
14 6C

Answer 19

6P,6N,6E
6P,7N,6E
6P,8N,6E

Question 20

Iron contains a mixture of 4 different isotopes 54 Fe, 56 Fe, 57 Fe and 58 Fe
State how these isotopes differ
State the similarity between these isotopes

Answer 20

Contains different number of neutrons

Nuclei contains same number of protons

Question 21

State the number of protons neutrons and electrons in the following isotopes
15 7N
109 47Ag
207 82Pb

Answer 21

P7,8N,7N
P47, N62, E47
P82, N125, E82

Question 22

State the number of protons, neutrons and election in the following ions:
41 19 K+
34 16 S2-
53 24 Cr3+

Answer 22

P19 N22 E18
P16 N18 E18
P24 N29 E21

Question 23

State the difference in the number of protons, neutrons and electrons of the following
6Li and 7Li
18O and 18O2-
39K+ and 40Ca2+

Answer 23

7Li has an extra neutron
18O2- has two more electrons
40Ca2+ as one more proton

Question 24

What is the mass of a Carbon-12 isotope

Answer 24

12u (units)

Question 25

What is relative atomic mass

Answer 25

The weighted mean mass of an atom of an element compared to 1/12th the mass of an atom of Carbon-12

Question 26

How is a mass spectrometer operated?

Answer 26

A sample is placed inside the spectrometer

The sample is vaporised and ionised to form positive ions

The ions are accelerated. Heavy ions move slower and are more difficult to deflect than lighter ions so the ions of each isotope are separated

The ions are detected on a mass spectrum as a mass-to-charge ratio m/z. Each ion reaching the detector adds to the signal, so the greater the abundance, the larger the signal

Question 27

Define the terms
Relative isotopic mass

Relative atomic mass

Answer 27

Mass of an isotope relative to 1/12th of the mass of an atom of Carbon-12

The weighted mean mass of an atom of an element relative to 1/12th the mass of an atom of Carbon-12

Question 28

What is a binary compound?

Answer 28

A compound that only contains two elements

Metal ion comes first, second element adds -ide

eg. Sodium Oxide

Question 29

What is a polyatomic ion?

Answer 29

An ion which may contain atoms of more than 1 element bonded together

eg. Ammonium Sulfate

Question 30

What is a diatomic molecule?

Answer 30

A molecule that exist as 2 atoms bonded together

Question 31

What are the state symbols used in chemical equations

Answer 31

g - gas
l - liquid
s - solid
aq - aqueous (dissolved in water)

Question 32

Write formulae for the following:
Potassium Oxide
Magnesium Iodide
Calcium Phosphide
Iron (III) Hydroxide
Ammonium Carbonate
Iron (II) Nitrate

Answer 32

K2O
MgI2
Ca3P2
Fe(OH)3
(NH4)2CO3
Fe(NO3)2

Question 33

Name Each compound from the formula
AlN
(NH4)3PO4
Fe2(SO4)3

Answer 33

Aluminium Nitride
Ammonium Phosphate
Iron (III) Sulfate