The number of Barr bodies in a $XXXX$ female is .....

In which of the following reactions is the product an ether?

$A$ gaseous mixture contains $50\%$ helium and $50\%$ methane by volume. Find the percentage by weight of methane in this gaseous mixture.

$A$ - Events after the formation of zygote are called post-fertilization events.
$R$ - In viviparous animals,a young one develops outside the mother's body.

Molar heat capacity $(C_p)$ of water at constant pressure is $75 \ J \ K^{-1} \ mol^{-1}$. The increase in temperature (in $K$) of $100 \ g$ of water when $1 \ kJ$ of heat is supplied to it is

What is obtained by the reaction of $HCOOH$ with concentrated $H_2SO_4$?