MEDIUM
AS and A Level
IMPORTANT
Earn 100
What is the general trend in first ionisation energies across Period 3?
Important Questions on Periodicity
MEDIUM
AS and A Level
IMPORTANT
Explain why aluminium has a lower first ionisation energy than magnesium.
MEDIUM
AS and A Level
IMPORTANT
Explain why sulphur has a lower first ionisation energy than phosphorus.
MEDIUM
AS and A Level
IMPORTANT
The first ionisation energies of the p-block elements are given in the table below. Predict the missing value for the first ionisation energy of selenium.
| p-block element of period 4 | Atomic number | First ionisation energy/ |
| gallium | 31 | 577 |
| germanium | 32 | 762 |
| arsenic | 33 | 966 |
| selenium | 34 | |
| bromine | 35 | 1140 |
| krypton | 36 | 1350 |
MEDIUM
AS and A Level
IMPORTANT
Which one of these statements about the periodicity of the Period 3 elements is correct?
MEDIUM
AS and A Level
IMPORTANT
The Group 1 metal lithium reacts in a similar way to sodium. It reacts with oxygen, producing lithium oxide. Write the balanced symbol equation, including state symbols, for this reaction.
MEDIUM
AS and A Level
IMPORTANT
Lithium also reacts with chlorine. Write the balanced symbol equation, including state symbols, for this reaction.
MEDIUM
AS and A Level
IMPORTANT
The Group 2 metal calcium reacts more vigorously with cold water than magnesium does, forming an alkaline solution. Write the balanced symbol equation, including state symbols, for this reaction.
MEDIUM
AS and A Level
IMPORTANT
The solution formed when of calcium react completely with of water is more alkaline than the solution formed when of magnesium react completely with of water. Explain why?
