Chemistry Revision Flashcards
Why are sodium and lithium both in group 1?
They have 1 electron in their outer shell & similar chemical properties.
When can ionic compounds conduct electricity?
Has to be a liquid that’s melted or dissolved in water
What is a ionic compound?
A product made up of ions
What is a ion?
An ion is a charged particle
What is a covalent bond?
shared electrons by shared shells e.g. water = 1 x oxygen atom and 2 x hydrogen atoms.
If an atom is in group 7, how many electrons will it have on its outer shell?
7
Complete the following word equation:
Magnesium carbonate + nitric acid =…….
What kind of reaction is this?
Magnesium nitrate + carbon dioxide + water
Which is an exothermic reaction
Calculate the relative formula mass for calcium carbonate CACO3
Ca = 40 C = 12 O = 16
CaCO3
= 40 + 12 + (16 x 3)
= 52 + 48
= 100g.
What does the term endothermic mean?
Keeps heat in and a reaction absorbs heat
Do simple covalent compounds have high or low melting points? explain.
A low melting point
What gas is produced when lithium is added to water?
Hydrogen
What is the charge of an electron and the mass of a neutron?
Electron charge = 1
Neutron mass = 1
Describe & explain the observations you would see when potassium bromide reacts with chlorine.
There would be a colour change.
The end colour would be orange/brown
The final products would be:
potassium chloride + bromide
Define electrolysis
Electrolysis is the splitting of a compound (containing ions) using electricity.
Why can simple covalent compounds not conduct electricity?
No free electrons therefore current cannot flow
Describe the number and position of particles in a nitrogen atom.
In the nucleus there are 7 protons and 7 neutrons. Orbiting the nucleus on shells there are 7 electrons. The electron configuration for nitrogen is 2.5.
Why are metals used for making wires and pans?
They have high melting points and are good at conducting electricity due to the delocalised electrons.
