Chemistry 1st Paper CQ-Dhaka Board-2017

What is a suspension?

Explain the role of chemistry in food security.

Explain the cleaning mechanism of cleaner '$'A'$.

Can the cleaner $'B'$be used as a toilet cleaner? Analyse with justification.

What is orbital?

What is the reason for stability of colloid?

Calculate the number of orbital of the outermost shell by calculating the value of $l$ and $\mathrm{m}$ in the stem $\mathrm{I}$.

Compare the atomic model of I and II in the stem.

Write down Hess's law.

Why is the neutralization enthalpy of a strong acid and a strong base is a constant value?

Describe with equations the identification of the cation of the container $\mathrm{K}$.

Does the addition of a small amount of strong acid or base change the $\mathrm{pH}$ of the solution of container-M?

What is periodic property?

Why is conc. $\mathrm{HCl}$ used in flame test?

Between $X$ and $Y$ which element has higher electron affinity? Explain.

Analyse the nature of the compounds formed between $Y$ and $P, Q, R$ separately.

What is a standard solution?

Explain the importance of optimum use of chemicals in the laboratory.

Calculate the pH of solution prepared by Anik.

Which of the two solutions is more acceptable as a standard solution? Justify your answer. 4 Answer to the question no.