chemistry test 1

Question 1

Name three properties of group 1 metals

Answer 1

Soft, Shiny, Low density, React with oxygen, Low melting and boiling points

Question 2

What happens to the reactivity of group one elements as you move down the group? Why?

Answer 2

The reactivity increases. This is because the elements have more electrons. Electrons are attracted to the positive nucleus and the further from the nucleus, the lesser the electrostatic attraction. If you have more electron shells, it interferes with the attraction because of electron shielding.

Question 3

What are properties of group 7 elements?

Answer 3

The are diatomic, have 7 electrons in their outer shells. They exist in different states at room temperature.

Question 4

What happens to the reactivity as you move down group 7? Why?

Answer 4

It decreases. Group 7 elements have 7 electrons in their outer shells, so they need to gain 1 more electron to have a full shell. As you move down the group, the number of electrons in the atoms of the elements increases, meaning they have more electron shells. This causes electron shielding because the electrostatic attraction between the negatively charged electrons and positive nucleus of the atom gets weaker. This makes it harder to gain electrons, so the reactivity decreases.