Chemical properties among elements (periodic table notes)

Question 1

How do alkali metals react with water and burn in oxygen

Answer 1

Vigorously and give off hydrogen gas; burn in oxygen strongly to form solid oxides

Question 2

Ionisation energy of alkali metals

Answer 2

ionisation energy low so very reactive, as we go down the group elements become more reactive as the ionisation energy is low

Question 3

Physical properties of alkali metals

Answer 3

Soft, low density, silver, low melting point

Question 4

How do alkali earth metals react with water and burn in oxygen?

Answer 4

Reaction with water varies: Be-not very reactive; Mg-slow with cold water fast with steam; Ca, Sr, Ba very reactive with cold water. They burn in oxygen to form solid oxides

Question 5

Ionisation energy of alkali earth metals

Answer 5

Reactivity increases down the group as shell sizes increase and ionisation energy decreases

Question 6

Physical properties of alkali earth metals

Answer 6

Silver, harder, denser and higher melting point than alkali metals

Question 7

Physical properties of halogens

Answer 7

Low melting and boiling points. At room temp, F2, Cl2-gases, Br2-liquid, I2-solid. Colour varies, F2-colourless, Cl2-green, Br2-red-brown, I2-purple-black

Question 8

How do we determine the reactivity of halogens

Answer 8

The electron affinity, which decreases down the group meaning the reactivity does too

Question 9

What are the properties of noble gases?

Answer 9

Full outer shell so not reactive. Low boiling point, colourless, gases at room temperature