Search our library of Chemistry A Level questions

Top answers

Chemistry

A Level

What does the strength of lattice enthalpy of formation depend on?

So, lattice enthalpy of formation is defined as the 'standard enthalpy change when one mole of an ionic crystal lattice is formed from its constituent ions in gase...

Answered by Zaynab A. • Chemistry tutor

2442 Views

Explain why the reactivity of Group 2 elements increases down the group.

Moving down Group 2, the atomic radius increases as there are more electron shells. This also means that the outermost electrons are more shielded from the positive charge of the nucleus. This decreases t...

Answered by Joe C. • Chemistry tutor

5974 Views

Describe a simple way to distinguish between aqueous solutions of potassium nitrate (KNO3) and potassium sulfate (K2SO4) using one test tube reaction

Add one of the following: barium chloride, barium hydroxide, barium nitrateObservation with potassium nitrate: colourless solution/ or no visible change or reaction) Observation with potassium sulfate: wh...

Answered by Rebecca S. • Chemistry tutor

8519 Views

What is Ionisation Energy and the three factors that affect it? 2)State and explain the general trend in first ionisation energies for the Period 3 elements.

Ionisation energy is the energy required to remove 1 mole of electrons from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous ions.For...

Answered by Kadambari R. • Chemistry tutor

12143 Views

Explain Le Chatelier's Principle

In a chemical equilibrium, the position of the equilibrium will always move to oppose any change in temperature, pressure or concentration of reactants/products. For example, if temperature is increased, ...

Answered by Jacob C. • Chemistry tutor

3063 Views