Group 2 Hydroxides

How are Hydroxides made

Group 2 element + water → hydroxides

E.g Be + H2*O → Be(OH)*2

How does Br react with water

Br does not react at all with water

How does Mg react with water

Mg reacts little bit with liquid water -

_{Mg reacts} vigorously _{with steam -}

What happens to reactivity down group 2 hydroxides

Reactivity increases down a group - sum of 1st and 2nd ionisation energy decreases therefore activation energy required to form a metal hydroxide decreases

What happens to solubility down group 2 hydroxides and why

Solubility increases as radius increases so weaker attraction between group 2 and OH- ions so less energy so more soluble

What is the anomaly for solubility down group 2

Calcium hydroxide is hardly soluble at all and so can be observed as a white precipitate

What is Magnesium hydroxide Mg(OH)2 used for? and why?

Heart burn - so Mg(OH)2 neutralizes pH of stomach

as very low solubility and weak base so will not damage body

What is Calcium Hydroxide Ca(OH)2 also known as

slaked lime

What is calcium hydroxide used for?

To neutralize soil

as it is readily available and strong base