When $100 \, mL$ of $1 \, M$ $NaOH$ and $10 \, mL$ of $10 \, N$ $H_2SO_4$ solutions are mixed,what will be the nature of the resulting solution?

Match the following columns:

Column - $A$	Column - $B$
$(A)$ $88 \ g$ of $CO_2$	$(1)$ $0.2 \ mol$
$(B)$ $6.022 \times 10^{23}$ molecules of water	$(2)$ $2 \ mol$
$(C)$ $5.6 \ L$ of $O_2$ at $STP$	$(3)$ $1 \ mol$
$(D)$ $96 \ g$ of $O_2$	$(4)$ $6.022 \times 10^{23}$ molecules
$(E)$ One mole of any gas at $STP$	$(5)$ $3 \ mol$

Assign $A, B, C, D$ from the given type of reaction.
$CaCl_2 + Na_2SO_4 \longrightarrow $ No reaction

What are the different elements present in the mineral barite?

Calculate the molarity of each of the following solutions: $(a)$ $30 \, g$ of $Co(NO_3)_2 \cdot 6H_2O$ in $4.3 \, L$ of solution $(b)$ $30 \, mL$ of $0.5 \, M \, H_2SO_4$ diluted to $500 \, mL$.

Mole fraction of $O_2$ in $O_2$ and $O_3$ mixture is $0.25$. Hence percentage concentration $\left( \frac{w}{W} \% \right)$ of $O_2$ in the mixture is: