Overall, the general trend is an increase across the period.
The decrease in shielding (as outer electrons are less influenced by the nucleus) is outweighed by an increased nuclear charge …
Working out the electronic configuration of an atom can be done in several ways, although the method I'll be demonstrating below is the fastest. If you have time at the …
Reactivity increases down the group.
This is because the outer electron in each atom is further away from the nucleus as you go down the group and so the electrostatic …
The material is made up from nylon laminated with a PTFE / polyurethane membrane. The membrane is too fragile on its own hence why it is combined with the …
The formula of the metal oxide is MO, which means there is only one oxygen atom bonded to the metal. The Mr of a compound is the sum of Ar …
An atom has the same number of protons and electrons so an atom has no overall electric charge.
If an atom loses or gains electrons it becomes an ion.
An …
The periodic table arranges all the different elements into columns and rows, The horizontal rows are called periods, this is where the elements differ from left to right but the …
Le Chatelier's principle is commonly known as the quilibrium law and it is useful in order to be able to analyse reversible reactions and how changing the conditions will affect …
Any chemical that dissociates to give an H+ ion is classified as an acid. There are stong and weak acids but at GCSE you only need to know some …
An easy way to remember the difference between Oxidation and Reduction is OIL RIG:
Oxidation
Is
Loss (of electrons)
Reduction
Gain (of electrons) …
When they react, both chlorine and bromine need to accept an electron into their outer electron shell to complete the shell and form chloride and bromide ions. There are three …
From the equation given in the question we can see that one mole of hydrochloric acid (HCl) reacts with one mole of sodium hydroxide (NaOH).
The first thing to do …
Polymers are large molecules made from lots of repeating units called monomers.
Plastic bags, waterproof coatings on clothes and wound dressings can all be made from polymers!
An atom is made up of electrons, protons and neutrons. Electrons have a negative charge (-1), protons have a postive charge (+1) and neutrons have a neutral charge.
Atoms must …
At dynamic equilibrium in a closed system (for example, in the Haber process to make ammonia), both the forward and backward reactions continue to occur. However, both reactions happen at …
concentration = moles / volume
must convert volume into litres 1 litre = 1000cm3 (divide by 1000)
c= n/v = 0.4/0.025 = 16mol/l
An Atom is made up of 3 parts, protons, neutrons and electrons. Each element has it's own number of protons and electrons which will always be the same number …
What you need for these equations are a calculator, periodic table and the following equation:
Mass (g) = Mr x Moles (important equation to remember)
In this case we already …
Alkanes are saturated because they contain only single covalent bonds. Alkenes are unsaturated because they do have double covalent bonds.
58.5
Relative formula mass (Mr) is found by adding together the relative atomic masses (Ar) of all the atoms present in a compound.
Sodium Chloride is …
