Which of the following gases could be collected by downward displacement of air?
Which of the following substances has the lowest boiling point?
The branch of science that deals with the nature and properties of substances and how one substance can be converted to another is known as
The electron configuration 1S\(^2\) 2S\(^2\) 2P\(_x\)\(^2\) contravenes the
The oxidation number of Chromium in Na\(_2\)Cr\(_2\)O\(_7\) is
