1e Chemical formulae, equations and calculations (p1)

Question 1

What is the charge on a hydrogen ion?

Answer 1

H+

Question 2

What is the charge on a magnesium ion?

Answer 2

Mg2+

Question 3

What is the charge on a barium ion?

Answer 3

Ba2+

Question 4

What is the charge on a copper(I) ion?

Answer 4

Cu+

Question 5

What is the charge on a copper(II) ion?

Answer 5

Cu2+

Question 6

What is the charge on a iron(II) ion?

Answer 6

Fe2+

Question 7

What is the charge on a iron(III) ion?

Answer 7

Fe3+

Question 8

What is the charge on a phosphide ion?

Answer 8

P3-

Question 9

What is the charge on an oxide ion?

Answer 9

O2-

Question 10

What is the charge on an Ammonium ion?

Answer 10

NH4 +

Question 11

What is the charge on a nitrate ion?

Answer 11

NO3 -

Question 12

What is the charge on a cyanide ion?

Answer 12

CN-

Question 13

What is the charge of a hydroxide ion?

Answer 13

OH-

Question 14

What is the charge of a carbonate ion?

Answer 14

CO3 2-

Question 15

What is the charge of a sulfate ion?

Answer 15

SO4 2-

Question 16

What is the charge on a peroxide ion?

Answer 16

O2 2-

Question 17

What is the charge on a hydrogen carbonate ion?

Answer 17

HCO3 -

Question 18

What is the charge on a hydrogen sulfate ion?

Answer 18

HSO4 -

Question 19

How to work out a chemical formula if the elements are metal and non metal?

Answer 19

1) Look at the elements in the compound.
- Metal and Non Metal
Ionic
Work out charges on each ion
Group 1 - 1+ 2 - 2+ 3 - 3+ 4 - * 5 - 5- 6 - 6- 7 - 7- 8 - **

Question 20

How to work out a chemical formula if the elements are 2 non metals?

Answer 20

1) Look at the elements in the compound
- Two or more non metals
Covalent
Work out how many covalent bonds each element must form
Group 4 (8-4) 4 5 (8-5) 3 6 (8-6) 2 7 (8-7) 1

Question 21

What are the diatomic elements?

Answer 21

H2, O2, N2, and group 7 elements F2, Cl2, Br2 and I2

Question 22

What is the formula of Hydrochloric acid?

Answer 22

HCl

Question 23

What is the formula of sulphuric acid?

Answer 23

H2SO4

Question 24

What is the formula of nitric acid?

Answer 24

HNO3

Question 25

What is the formula of sodium carbonate?

Answer 25

Na2CO3

Question 26

What is the formula of sodium sulphate?

Answer 26

Na2SO4

Question 27

What is the formula of Sodium nitrate?

Answer 27

NaNO3

Question 28

What is the formula of sodium hydroxide?

Answer 28

NaOH

Question 29

What is the formula of magnesium hydroxide?

Answer 29

Mg(OH)2

Question 30

What is the formula of calcium carbonate?

Answer 30

CaCO3

Question 31

What is the formula of ammonium cloride?

Answer 31

NH4Cl

Question 32

What is an element?

Answer 32

a substance made from one type of atom. It cannot be broken down into anything simpler by chemical means

Question 33

What is an atomic number?

Answer 33

Number of protons in the nucleus of an atom

Question 34

What is a mass number?

Answer 34

The number of protons and neutrons in the nucleus of an atom

Question 35

What is an isotope?

Answer 35

Atoms of an element with different numbers of neutrons but the same number of protons

Question 36

What is the Relative atomic mass? (Ar)

Answer 36

The mass of an atom of an element compared to the mass of an atom of a carbon. The relative atomic mass of carbon is defined as 12. This takes into account the abundance of all existing isotopes of that element.

Question 37

What is the Relative formula mass?

Answer 37

The combined relative atomic masses of all the atoms in a formula. To find the relative formula mass of a chemical you just add up the relative atomic masses of the constituent atoms.

Question 38

What is a mole?

Answer 38

An amount of substance containing 6x10 23 particles (atoms, molecules, ions). Note: One mole of a substance is equal to its relative atomic or formula mass in grams

Question 39

What is the equation for moles?

Answer 39

Moles = mass/relative atomic mass

Question 40

What is the molar volume of gasses?

Answer 40

1 moles of any gas occupies 24000cm3 at room temperature and pressure

Question 41

What is the equation for #moles of gas?

Answer 41

moles gas = volume dm3/24

Question 42

How do you convert from cm3 to dm3?

Answer 42

To convert cm3 to dm3 divide by 1000

Question 43

What is thermal decomposition?

Answer 43

Breaking down by heat

Question 44

What is the equation for the percentage yield?

Answer 44

Percentage yield = actual value/theoretic value x 100

Question 45

What is an empirical formula?

Answer 45

Shows the simplest ratio of atoms present

Question 46

What is the molecular formula?

Answer 46

Tells you the actual number of atoms in one molecule

Question 47

What is the empirical and molecular formula of ethane?

Answer 47

Empirical formula - CH3 Molecular formula - C2H6

Question 48

How do you convert from empirical to molecular formula?

Answer 48

To convert from empirical to molecular formula you need to know the Mr of the actual compound and then work out the Mr of the empirical formula SO - Actual Mr/Empirical Mr = multiplying factor Now multiply each part of the empirical formula by the scale factor

Question 49

How to calculate reacting mass calculations?

Answer 49

1) Write