electronic configuration

Question 1

electronic configuration rule?

Answer 1

2,8,8

Question 2

define ‘isotopes’

Answer 2

atoms of the same element with different numbers of neutrons. the isotopes of an element have the same number of protons.

Question 3

pattern down a group and across a period

Answer 3

down group = +1 outer shell
across period = +1 electron

Question 4

Practice question: state why argon is used in a light bulb. explain your answer in terms of the electronic structure of an argon atom. (3)

Answer 4

argon is a noble gas/ group 0 element, therefore, it has full outer shells. noble gases are unreactive and stable. it does not gain, lose or share electrons, making it a suitable element to be used in a light bulb.

Question 5

Practice question: two isotopes of oxygen are oxygen-16 and oxygen-18. explain, in terms of particles, how the nucleus of an oxygen-18 atom is different from the nucleus of an oxygen-16 atom. (2)

Answer 5

Although they are the same element, they have different numbers of neutrons. (O¹⁸ has 10 neutrons, and O¹⁶ has 8 neutrons.) However, the protons stay the same.

Question 6

noble gases facts

Answer 6

• have full outer shells
• do not need to gain, lose, or share electrons
• very stable, most unreactive (inert) of the elements
• don’t normally form bonds with other elements