Symbols, Formulae & Equations Flashcards
What is a Chemical Symbol?
3 marks
- Represents each Element in the Periodic Table.
- Has 1-2 letters; first letter must be a capital, second letter must be lower case.
Give an example of a Chemical Symbol.
2 marks
Mg is the correct symbol for magnesium, but mg, mG and MG are wrong.
Describe Diatomic Elements.
4 marks
- The formulae for most elements is just their symbol, except some Non-Metal Elements known as Diatomic Elements .
- They contain 2 Atoms of the Same Element Covalently Bonded together.
What are Diatomic Elements?
3 marks
Diatomic Elements are Non-Metal Elements that contain 2 Atoms of the Same Element Covalently Bonded together.
Give the Molecular formula of the following Diatomic Elements.
Hydrogen, Nitrogen, Oxygen, Fluorine, Chlorine, Bromine, Iodine, Astatine
(8 marks)
Hydrogen - H2 Nitrogen - N2 Oxygen - O2 Fluorine - F2 Chlorine - Cl2 Bromine - Br2 Iodine - I2 Astatine - At2
Give the Molecular formula of Hydrogen (Diatomic Element).
1 mark
H2
Give the Molecular formula of Nitrogen (Diatomic Element).
1 mark
N2
Give the Molecular formula of Oxygen (Diatomic Element).
1 mark
O2
Give the Molecular formula of Fluorine (Diatomic Element).
1 mark
F2
Give the Molecular formula of Chlorine (Diatomic Element).
1 mark
Cl2
Give the Molecular formula of Bromine (Diatomic Element).
1 mark
Br2
Give the Molecular formula of Iodine (Diatomic Element).
1 mark
I2
Give the Molecular formula of Astatine (Diatomic Element).
1 mark
At2
Give the Diatomic Element from each of the Molecular Formulae.
H2, N2, O2, F2, Cl2, Br2, I2, At2
(8 marks)
H2 - Hydrogen N2 - Nitrogen O2 - Oxygen F2 - Fluorine Cl2 - Chlorine Br2 - Bromine I2 - Iodine At2 - Astatine
Give the Diatomic Element from the Molecular Formulae: H2
1 mark
Hydrogen
Give the Diatomic Element from the Molecular Formulae: N2
1 mark
Nitrogen
Give the Diatomic Element from the Molecular Formulae: O2
1 mark
Oxygen
Give the Diatomic Element from the Molecular Formulae: F2
1 mark
Fluorine
Give the Diatomic Element from the Molecular Formulae: Cl2
1 mark
Chlorine
Give the Diatomic Element from the Molecular Formulae: Br2
1 mark
Bromine
Give the Diatomic Element from the Molecular Formulae: I2
1 mark
Iodine
Give the Diatomic Element from the Molecular Formulae: At2
1 mark
Astatine
What are used all over the world, no matter which language is spoken?
(1 mark)
The same chemical symbols.
What does a formula do?
3 marks
A formula gives information about the type and the number of each atom present in a Compound.
What does the Formula for Sodium Sulfate (Na2SO4) tell you about what it Contains.
is Na2SO4. It tells you that sodium sulfate contains:
(3 marks)
- 2 Sodium Atoms
- 1 Sulfur Atom
- 4 Oxygen Atoms
What do the Subscript Numbers refer to?
2 marks
The Subscript Numbers refer to the Element before them.
- If there is just 1 Atom in the Formula a 1 is not written.
Sometimes a Formula includes Brackets.
How are they used?
(2 marks)
The Atoms inside the brackets are multiplied by the number outside the brackets.
Aluminium sulfate’s formula is Al2(SO4)3.
What does it contain?
(3 marks)
- 2 atoms of aluminium
- 3 atoms of sulfur
- 12 atoms of oxygen
Give the Formulae for the following Compounds.
Water, Carbon Monoxide, Carbon Dioxide, Sulfur Dioxide, Sulfur Trioxide
(5 marks)
Water - H20 Carbon Monoxide - CO Carbon Dioxide - CO2 Sulfur Dioxide - SO2 Sulfur Trioxide - SO3