A …… lens is used to correct myopia and a ….. lens is used to correct hypermetropia. A Concave, concave B Convex, convex C Convex, concave D Concave, convex
Rate of reaction of any substance depends on (A) active mass (B) molecular weight (C) atomic weight (D) equivalent weight
Formula of oleum is (A) $\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{7}$ (B) $\mathrm{H}_{2} \mathrm{SO}_{4}$ (C) $\mathrm{H}_{2} \mathrm{SO}_{3}$ (D) $\mathrm{H}_{2} \mathrm{SO}_{5}$
Find the shortest distance between the given lines. $$ \begin{array}{l} \square \vec{r}=(\hat{i}+\hat{j})+\lambda(2 \hat{i}-\hat{j}+\hat{k}) \\ \vec{r}=(2 \hat{i}+\hat{j}-\hat{k})+\mu(3 \hat{i}-5 \hat{j}+2 \hat{k}) \end{array} $$
Which of the following compounds has tetrahedral geometry? (a) $\left[\mathrm{Ni}(\mathrm{CN})_{4}\right]^{-2}$ (b) $\left[\mathrm{Pd}(\mathrm{CN})_{4}\right]^{2-}$ (c) $\left[\mathrm{PdCl}_{4}\right]^{2-}$ (d) $\left[\mathrm{NiCl}_{4}\right]^{2}$