In 1800 how many elements were known ?Which oxide is amphoteric in nature?
Classification of element and periodicity in properties 1. In 1800 how many elements were known ? A 31 B 35 C 53 D 30 2. Which group of elements indicate the doberenier triads ? A Ca,Sr,Na B Li,Na,Ba C Li,Na,K D Cl,Br,F 3. Which Medal is given by the royal society of London to newlands […]