What happens chemically when quicklime is added to water filled in a bucket ?
When Calcium oxide i.e. quick lime is added to water filled in a bucket, it reacts vigorously with water to produce slaked lime (calcium hydroxide) releasing a large amount of heat.
Quick lime (calcium oxide, CaO) readily forms calcium hydroxide(slaked lime) as shown:
CaO+H2O→Ca(OH)2