The electronic configuration of an element is 1S2 2S2 2P6 3S2 3P3. How many unpaired electrons are there in the element?
The best treatment for a student who accidentally poured conc tetraoxosulphate(vi) on his skin in the laboratory is to wash his skin with?
A. with cool running water
B. sodium hydroxide solution
C. iodine solution
D. sodium trioxonitrate(v) solution
When water drops are added to calcium carbide in a container and the gas produced is passed through a jet and lighted, the resultant flame is called an?
B. Oxyhydrocarbon flame
C. Oxyacetylene flame
D. Oxymethane flame
How many valence electrons are contained in the element 31/15P ?
The chlorinated alkane often used industrially to remove grease is?
When a solid substance disappears completely as a gas on heating, the substance is said to have undergone?