Chemical Formulae & Equations

Question 1

What are the 2 main types of chemical bonds?

Answer 1

Ionic and covalent bonds

Question 2

What types of elements are involved in ionic bonding?

Answer 2

In ionic bonding, a metal and non-metal are involved.

Question 3

How does ionic bonding work?

Answer 3

Ionic bonding works by the transfer of electrons from the metal to the non-metal element, in order for both to achieve the duplet/octet electronic configuration.

Question 4

What types of elements are involved in covalent bonding?

Answer 4

Covalent bonding occurs between non-metals.

Question 5

How does covalent bonding work?

Answer 5

Covalent bonding works by sharing electrons between non-metal elements, in order for both to achieve the duplet/octet electronic configuration.

Question 6

What is the chemical formula of a sodium ion?

Answer 6

Na^+

Question 7

What is the chemical formula of a magnesium ion?

Answer 7

Mg^2+

Question 8

What is the chemical formula of an iron (II) ion?

Answer 8

Fe^2+

Question 9

What is the chemical formula of an iron (III) ion?

Answer 9

Fe^3+

Question 10

What is the chemical formula of a copper (II) ion?

Answer 10

Cu^2+

Question 11

What is the chemical formula of a zinc ion?

Answer 11

Zn^2+

Question 12

What is the chemical formula of a silver ion?

Answer 12

Ag^+

Question 13

What is the chemical formula of an aluminium ion?

Answer 13

Al^3+

Question 14

What is the chemical formula of a nitrogen ion?

Answer 14

N^3-

Question 15

What is the chemical formula of a sulfur ion?

Answer 15

S^2-

Question 16

What is the chemical formula of an oxygen ion?

Answer 16

O^2-

Question 17

What is the chemical formula of a chloride ion?

Answer 17

Cl^-

Question 18

What is the chemical formula of a bromide ion?

Answer 18

Br^-

Question 19

What is the chemical formula of an iodide ion?

Answer 19

I^-

Question 20

What is the chemical formula of a sulfate ion?

Answer 20

SO4^2-

Question 21

What is the chemical formula of a nitrate ion?

Answer 21

NO3^-

Question 22

What is the chemical formula of a carbonate ion?

Answer 22

CO3^2-

Question 23

What is the chemical formula of an ammonium ion?

Answer 23

NH4^+

Question 24

What is the chemical formula of a hydroxide ion?

Answer 24

OH-

Question 25

What is the chemical formula of a phosphate ion?

Answer 25

PO4^3-

Question 26

What is the charge of a compound?

Answer 26

A compound's net/total charge should always add up to zero. Hence, all ions that make up the compound should have charges that add up to zero to ensure it is balanced.

Question 27

What does the prefix (bigger number before the compound/element) at the front of a compound/element represent?

Answer 27

It represents the number of moles of the entire compound/element. Eg. 4HCl --> there are 4 moles of the entire hydrogen chloride compound.

Question 28

What does the suffix (smaller number on the right of some elements in a compound) represent?

Answer 28

It represents the number of moles of the element that is in 1 mole of compound. Eg. CaCl2 --> there are 2 moles of chlorine element in every 1 mole of the calcium chloride compound.

Question 29

Write a balanced equation between hydrochloric acid and sodium hydroxide, which produces sodium chloride and water.

Answer 29

NaOH (aq) + HCl (aq) --> NaCl (aq) + H2O (l)

Question 30

Write a balanced equation between iron (III) oxide and carbon, which produces metal iron and carbon dioxide.

Answer 30

2Fe2O3 (s) + 3C (s) --> 4Fe (s) + 3CO2 (g)

Question 31

Write a balanced equation between nitric acid and magnesium hydroxide, which produces magnesium nitrate and water.

Answer 31

4HNO3 (aq) + 2Mg(OH)2 (aq) --> 2Mg(NO3)2 (aq) + 4H2O (l)

Question 32

Write a balanced equation between metal calcium and hydrochloric acid, which produces calcium chloride and hydrogen gas.

Answer 32

Ca (s) + 2HCl (aq) --> CaCl2 (aq) + H2 (g)

Question 33

Write a balanced equation between sulfuric acid and potassium hydroxide, which produces potassium sulfate and water.

Answer 33

H2SO4 (aq) + 2KOH (aq) --> K2SO4 + 2H2O (l)

Question 34

Write a balanced equation between propane (C3H8) and oxygen gas, which produces carbon dioxide and water.

Answer 34

C3H8 (aq) + 5O2 (g) --> 3CO2 (g) + 4H2O (l)