10. Group 2 Flashcards
Reaction of Mg with oxygen
- burns in oxygen on heating with a white flame
- white MgO solid formed
Reaction of Ca with oxygen
- burns in oxygen on heating with a brick-red flame
- white CaO solid formed
Reaction of Sr with oxygen
- burns in oxygen on heating with a red flame
- white SrO solid formed
Reaction of Ba with oxygen
- burns in oxygen on heating with a green flame
- white BaO solid formed
Reaction of Mg with water
- reacts very slowly with cold water to form a white precipitate of Mg(OH)2
- effervescence due to hydrogen gas - reacts vigorously with steam and burns with a white flame to form white MgO solid
- effervescence due to hydrogen gas
Reaction of Ca with water
- forms a cloudy white suspension of slightly soluble Ca(OH)2 / water turns milky
- bubbles produced
- calcium sinks
- calcium gets smaller / disappears
Reaction of Sr with water
- faster bubbling
- faster disappearance of Sr
- no precipitate is formed in excess water
Reaction of Ba with water
- even faster bubbling
- even faster disappearance of Ba
- no precipitate is formed in excess water
Reaction of Group 2 elements with dilute hydrochloric acid / dilute nitric acid
- all react with dilute HCl/HNO3 to give bubbles of hydrogen and a colourless solution of the metal chloride / metal nitrate
- reaction becomes more vigorous down the group
Reaction of Mg with dilute sulfuric acid
- bubbles of hydrogen gas produced
- colourless solution of MgSO4 formed
Reaction of Ca with dilute sulfuric acid
- some bubbles of hydrogen gas produced
- white precipitate of CaSO4 formed, which is sparingly soluble
Reaction of Sr with dilute sulfuric acid
- very slight bubbles of hydrogen gas produced
- white precipitate of SrSO4 formed, which is insoluble
Reaction of Ba with dilute sulfuric acid
- very slight bubbles of hydrogen gas produced
- white precipitate of BaSO4 formed, which is insoluble
Reaction of MgO with water
- sparingly soluble / insoluble in water to form a white precipitate of Mg(OH)2 and a weakly alkaline solution, pH=9
Reaction of CaO with water
- slightly soluble in water to form milky solution and an alkaline solution, pH=11