chem

Question 1

(b) Why is aluminium positioned in Group 3 of the periodic table?

Answer 1

has three electrons in outer energy level / shell
allow electronic structure is 2.8.3

Question 2

What colour is KCl

Answer 2

brown

Question 3

What are the observations in a reaction

Answer 3

effervescence / bubbling / fizzing / bubbles of gas
do not accept just gas alone
1
magnesium gets smaller / disappears

Question 4

Explain how a covalent bond holds two atoms together.

Answer 4

electrostatic force of attraction between shared pair of negatively charged electrons
1
and both positively charged nuclei

Question 5

Other substances are added to silicon dioxide to make glass. Glass melts at a lower
temperature than silicon dioxide.
Suggest why.

Answer 5

weaker bonds

fewer bonds

disruption to lattice

Question 6

Describe the structure of a metal. (3)

Answer 6

lattice / regular pattern / layers / giant structure / close-packed arrangement
1
(of) positive ions or (of) atoms
1
(with) delocalised / free electrons