Group 2 - physical properties

Question 1

What is the electron arrangement of atoms? How does it change down the group?

Answer 1

2 electrons in an outer s-orbital

the s-orbital becomes further away form the nucleus going down the group

Question 2

How does the size of the atoms change going down the group?

Answer 2

the atoms get bigger going down the group the atomic radii increase because each element has an extra filled main level of electrons compared to the atoms above it

Question 3

How does the melting points change down the group?

Answer 3

high melting points the sea of delocalised electrons are further away from the positive nuclei

as a result, the strength of the metallic bonds decreases going down the group the melting points decrease going down the group

Question 4

What is the exception to the trend in boiling points?

Answer 4

magnesium, with the lowest melting point does not fit the trend

Question 5

How many electrons do group 2 elements loose in their rections?q

Answer 5

loose two electrons to become ions with a charge of +2

Question 6

What is the energy need to be equal to in order for a reaction to occur?

Answer 6

the first two ionisation energies of the atom

Question 7

What is the trend in ionisation energies going down the group?

Answer 7

first and second ionisation energy decrease going down to group

Question 8

Why does this trend occur in IE

Answer 8

it takes less energy to remove the electrons as they become further and further away from the positive nucleus

the nucleus is more effectively shielded by more inner shells of electrons

Question 9

What is the equation for the neutralisation reaction of calcium oxide (lime) and calcium hydroxide (slaked lime)?

Answer 9

CaO (s) + 2HCl (aq) → CaCl₂ (aq) + H₂O (l)

Ca(OH)₂ (s) + 2HCl (aq) → CaCl₂ + 2H₂O (l)