Heat required to melt $1\, g$ of ice is $80\, cal$. $A$ man melts $60\, g$ of ice by chewing in one minute. His power is ........ $W$.

In which of the following reactions,chlorine acts as an oxidising agent?
$(i)$ $CH_3CH_2OH + Cl_2 \longrightarrow CH_3CHO + HCl$
$(ii)$ $CH_3CHO + Cl_2 \longrightarrow CCl_3CHO + HCl$
$(iii)$ $CH_4 + Cl_2 \xrightarrow{hv} CH_3Cl + HCl$
The correct answer is

$A$ student has to answer $10$ out of $13$ questions in an examination,choosing at least $5$ questions from the first $6$ questions. The number of choices available to the student is:

Which of the following halogen oxides is ionic?

The eccentricity of the conic $36x^2 + 144y^2 - 36x - 96y - 119 = 0$ is

The abundance of a species population within its habitat is called