chemistry - topic 4: predicting reactants and products

Why do some elements have similar characteristics?

They have the same number of outer shell electrons.

What are the elements in Group 1 known as?

Alkali Metals

What are the properties of alkali metals? (4 points)

• Soft (can be cut with a knife)

• Low MP

• Low density

• Very reactive

Do alkali metals get more or less reactive as you go down the group? Why?

More reactive (less energy needed to overcome the attractive forces between outer electron and nucleus)

Alkali metals react vigorously with // and // .

Water and oxygen.

Alkali metal + water = ?

Alkali hydroxide + hydrogen gas

Alkali metal + acid = ?

Salt + hydrogen gas

What are the elements in Group 7 known as?

Halogens

Halogens exist as // molecules.

Diatomic

What do chlorine, iodine, and bromine look like at room temperature?

Chlorine: Poisonous and reactive green gas

Iodine: Crystalline purple-black solid

Bromine: Dense and poisonous red-brown liquid

Do halogens get more or less reactive as you go down the group? Why?

Less reactive (harder to attract an electron when it’s further away from the nucleus).

Halogen + alkali metal = ?

Salt (metal halides)

What happens in a halogen displacement reaction?

A more reactive halogen displaces a less reactive halogen.

What are the elements in Group 0 known as?

Noble gases

Noble gases exist as // atoms.

Monatomic

Why are noble gases inert?

Full stable outer-shell of electrons.

Properties of noble gases: (2 points)

• Low MP and BP

• Low density