Which atom has the greatest first ionisation energy?
A H
B He
C Li
D Ne - AQA - A-Level Chemistry - Question 14 - 2019 - Paper 3
Question 14
Which atom has the greatest first ionisation energy?
A H
B He
C Li
D Ne
Worked Solution & Example Answer:Which atom has the greatest first ionisation energy?
A H
B He
C Li
D Ne - AQA - A-Level Chemistry - Question 14 - 2019 - Paper 3
Step 1
Identify the atoms and their position in the periodic table
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The atoms listed are H (Hydrogen), He (Helium), Li (Lithium), and Ne (Neon). These atoms are located in different groups of the periodic table, with Helium and Neon being noble gases known for high ionisation energies.
Step 2
Understand ionisation energy trends
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Ionisation energy generally increases across a period from left to right due to increased nuclear charge, which holds the electrons more tightly. It also tends to decrease down a group as additional electron shells increase the distance of the outermost electrons from the nucleus.
Step 3
Analyze the options provided
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Given the provided options, He (Helium) is a noble gas with a complete outer shell, making it highly stable and requiring a significant amount of energy to remove an electron. In contrast, H, Li, and Ne have lower ionisation energies compared to He.
Step 4
Conclusion
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Therefore, the atom with the greatest first ionisation energy is B He.
