Chemistry 1st Paper CQ-Barishal Board-2023

What is chemical bonding?

Explain the co-ordination bond in $\mathrm{NH}_{4}^{+}$ion.

At equilibrium the concentration of $\mathrm{PCl}_{5}$ is $0.2065 \mathrm{~mol} / \mathrm{L}$. Calculate the concentration of other two components.

To which side the stem reaction will be proceded? Analyze.

What is electronegativity of element?

Why ${ }_{6}^{14} \mathrm{C}$ and ${ }_{8}^{16} \mathrm{O}$ are the isotone isotone of each other? Explain.

Which one between $\mathrm{D}_{2} \mathrm{X}$ and $\mathrm{DG}$ has the higher melting point? Expalin.

Which one between the compound $\mathrm{E}_{2} \mathrm{X}$ and $\mathrm{EG}$ is more covalent in nature? Analyze.

What is antimicrobial?

Explain the role of salt in the food preservation.

Calculate the $\mathrm{K}_{\mathrm{P}}$ of the reaction (i) when $3.85 \%$ of $\mathrm{NH}_{3}$ is obtained in the equilibrium at $400^{\circ} \mathrm{C}$ and $10 \mathrm{~atm}$ presure.

Analyze the conditions for increasing the product of the reactions (i) and (ii).

What is transition element?

How is hydrogen spectrum formed? Explain.

Calculate the $\mathrm{pH}$ of the solution in pot-X.

Which one between $\mathrm{D}$ and $\mathrm{E}$ will act as buffer solution? Analyze it mathematically.

State the law of mass action.

What is meant by acidity is of $\mathrm{Al}_{2} \mathrm{O}_{3}$ 6? Explain.

Determine the largest wavelength of line spectrum when electrons are transferred to ' $\mathrm{B}$ ' energy leve.

Energy difference between 'A' and ' $\mathrm{C}$ ' energy level is $1.93 \times 10^{-18} \mathrm{~J}$. Explain mathematically whether the radiated light will be visible or not.