The function $f(x) = |x| + \frac{|x|}{x}$ is

For the electrochemical cell, $Mg ( s )\left| Mg ^{2+}( aq , 1 M ) \| Cu ^{2+}( aq , 1 M )\right| Cu ( s )$ the standard emf of the cell is $2.70 V$ at $300 K$. When the concentration of $Mg ^{2+}$ is changed to $x M$, the cell potential changes to $2.67 V$ at $300 K$. The value of $x$ is.

(given, $\frac{ F }{ R }=11500 K V ^{-1}$, where $F$ is the Faraday constant and $R$ is the gas constant, The value of $\ln (10)=2.30$ )

On heating ammonium dichromate,the gas evolved is

The complete set of values of $x$ for which the function $f(x) = 2 \ln(x-2) - x^2 + 4x + 1$ is increasing is:

Crystalline sodium chloride is an insulator of electricity because $......$

Read the following five statements $(1-5)$ carefully and answer the question that follows.
$(1)$ In $Equisetum$,the female gametophyte is retained on the parent sporophyte.
$(2)$ In $Ginkgo$,the male gametophyte is not independent.
$(3)$ The sporophyte of $Polytrichum$ is more developed than that of $Riccia$.
$(4)$ Sexual reproduction in $Volvox$ is isogamous.
$(5)$ Spores of slime molds lack a cell wall.
How many of the above statements are correct?