Chemistry 1st Paper MCQ-Dinajpur Board-2017

1. What is the $\mathrm{pH}$ of ethanoic acid $\left(\mathrm{K}_{2}=\right.$ $1.8 \times 10^{-5}$ )?

2. $50 \mathrm{~mL}$ of $0.175 \mathrm{M}$ HCOOH $\left(\mathrm{K}_{a}=1.8 \times\right.$ $\left.10^{-4}\right)$ solution is added to $50 \mathrm{~mL} 0.09 \mathrm{M}$ $\mathrm{NaOH}$. What is the $\mathrm{pH}$ of the solution?

3. Applicable to $R_{1}$ value -

i. ratio of distances covered by solute & solvent

ii. ratio of distances covered by solvent and salute

iii. the value is less than 1

Which one is correct?

4. The best chromatographic method for the separation of components for the mixture of amino acids and carbohydrates is -

5. Which of the aqueous solution of the following oxides has a $\mathrm{pH}$ greater than 7.0?