# SubSpecPoint

## 1:14a know what is meant by the terms atom

Atom: An atom is the smallest part of an element.

2019-05-23T15:17:51+00:00Categories: Uncategorized||

## 1:16a know what is meant by the terms atomic number, mass number and relative atomic mass (Aᵣ)

Atomic number: The number of protons in an atom.

Mass number: The number of protons and neutrons in an atom.

Relative atomic mass (Ar): The average mass of an atom compared to 1/12th the mass of carbon-12.

2019-05-23T15:18:05+00:00Categories: Uncategorized||

## 1:20a understand how to use electrical conductivity to classify elements as metals or non-metals

Metals

• conduct electricity

Non – Metals

• do not conduct electricity (except for graphite)

2019-05-23T15:18:19+00:00Categories: Uncategorized||

## 1:31a understand how the formulae of simple compounds can be obtained experimentally, including metal oxides

Finding the formula of a metal oxide experimentally

The formulae of metal oxides can be found experimentally by reacting a metal with oxygen and recording the mass changes.

Example: When magnesium is burned in air, it reacts with oxygen (O2) to form magnesium oxide (MgO).

Method:
• Weigh a crucible and lid
• Place the magnesium ribbon in the crucible, replace the lid, and reweigh
• Calculate the mass of magnesium
(mass of crucible + lid + Magnesium – mass of crucible + lid)
• Heat the crucible with lid on until the magnesium burns
(lid prevents magnesium oxide escaping therefore ensuring accurate results)
• Lift the lid from time to time (this allows air to enter)
• Stop heating when there is no sign of further reaction
(this ensures all Mg has reacted)
• Allow to cool and reweigh
• Repeat the heating , cooling and reweigh until two consecutive masses are the same
(this ensures all Mg has reacted and therefore the results will be accurate)
• Calculate the mass of magnesium oxide formed (mass of crucible + lid + Magnesium oxide – mass of crucible + lid)

2019-05-23T15:22:37+00:00Categories: Uncategorized||

## 1:38a understand how to use the charges of these ions in ionic formulae: metals in Groups 1, 2 and 3, non-metals in Groups 5, 6 and 7, Ag⁺, Cu²⁺, Fe²⁺, Fe³⁺, Pb²⁺, Zn²⁺, hydrogen (H⁺), hydroxide (OH⁻), ammonium (NH₄⁺), carbonate (CO₃²⁻), nitrate (NO₃⁻), sulfate (SO₄²⁻)

When given this information of the following ions, it is possible to work out the formulae of ionic compounds which include these ions.

Name of IonFormulaCharge
SulfateSO42--2
CarbonateCO32--2
NitrateNO3--1
HydroxideOH--1
AmmoniumNH4++1
Silver ionAg++1
Zinc ionZn2++2
Hydrogen ionH++1
Copper (II) ionCu2++2
Iron (II) ionFe2++2
Iron (III) ionFe3++3

Ion charges on the periodic table

2022-12-08T10:17:11+00:00Categories: Uncategorized||

## 2:44a describe tests for these gases: hydrogen, carbon dioxide

Test for hydrogen gas (H2)

• Test: use a lit splint
• Result: burns with a squeaky pop

Test for carbon dioxide (CO2)

• Test: bubble through limewater
• Result: limewater turns cloudy

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Section 1: Principles of chemistry

a) States of matter

b) Atoms

c) Atomic structure

d) Relative formula masses and molar volumes of gases

e) Chemical formulae and chemical equations

f) Ionic compounds

g) Covalent substances

h) Metallic crystals

i) Electrolysis

Section 2: Chemistry of the elements

a) The Periodic Table

b) Group 1 elements: lithium, sodium and potassium

c) Group 7 elements: chlorine, bromine and iodine

d) Oxygen and oxides

e) Hydrogen and water

f) Reactivity series

g) Tests for ions and gases

Section 3: Organic chemistry

a) Introduction

b) Alkanes

c) Alkenes

d) Ethanol

Section 4: Physical chemistry

a) Acids, alkalis and salts

b) Energetics

c) Rates of reaction

d) Equilibria

Section 5: Chemistry in industry

a) Extraction and uses of metals

b) Crude oil

c) Synthetic polymers

d) The industrial manufacture of chemicals

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