List of top Chemistry Questions

An acid `X' is prepared by acidifying an aqueous solution of borax. Which of the following statements are true for `X'?
I. It is white liquid with soapy touch
II. It is sparingly soluble in water
III. It is strong monobasic acid
IV. It acts as Lewis acid

The alloy of Li with 'X' is used to make armour plates. What is 'X'?

Ions of an element X is required for interneuronal transmission. Ions of an element Y helps in the transport of sugars into cells. X and Y are respectively

Observe the following unbalanced equations:
(I) $H_2O(l) + Na(s) \rightarrow$
(II) $H_2O(l) + F_2(g) \rightarrow$
Identify the correct statement.

At $27^\circ C$, the $K_a$ of acetic acid is $1.8 \times 10^{-5}$. What is the percentage of ionization of 0.02M of this acid at $27^\circ C$?

Observe the following equation
$H_2O_2(g) \rightarrow 2H(g) + 2O(g)$; $\Delta_a H^\ominus = 1066 \, kJ mol^{-1}$.
If $\Delta_{O-H} H^\ominus$ is $464 \, kJ mol^{-1}$, then $\Delta_{O-O} H^\ominus$ (in $kJ mol^{-1}$) value will be

A hydrocarbon containing C and H has 75% (by weight) of carbon. 32g of this hydrocarbon was completely burnt in air. What is the weight (in kg) of $CO_2$ formed?

The isobar of one mole of an ideal gas was obtained at P atm. The slope of the isobar is $0.82 L K^{-1}$. What is P (in atm)?

Consider the following statements
Statement I: The electronic configuration of $N_2$ in terms of molecular orbital theory is $KK (\sigma 2s)^2 (\sigma^* 2s)^2 (\pi 2p_x)^2 (\pi 2p_y)^2 (\pi 2p_z)^2$.
Statement II: According to molecular orbital theory, the double bond in $C_2$ molecule consists of two $\pi$ bonds.
The correct answer is

The correct order of bond angle of $HgCl_2 (A)$, $NH_3 (B)$, $H_2O (C)$ is

Which of the following sets are correctly matched?

Among the following the isoelectronic species are
I. $Mg^{2+}, Al^{3+}, F^-$
II. $O^{2-}, F^-, N^{3-}$
III. $K^+, Ca^{2+}, Sc^{3+}$
IV. $Mn^{2+}, Fe^{3+}, V^{3+}$

The emission spectrum of hydrogen contains a few lines. The energy ($\Delta E$) of one of the lines is $0.4578 \times 10^{-18}J$. The $n_1$ and $n_2$ belonging to this line are respectively

Identify the correct statements:
I. In the visible spectrum, violet light has highest frequency and red light has lowest frequency.
II. When white light is passed through a prism, violet light is deviated the most and red light is deviated the least.
III. Hydrogen atoms in gas phase exhibit line spectrum.

The sequence of reagents required to convert benzoic acid to n-propyl benzene is

What are X and Y respectively in the following set of reactions?

An alcohol X (C$_4$H$_{10}$O) reacts with Conc.HCl/ZnCl$_2$ to give corresponding chloride. X on dehydration forms Y, which reacts with Baeyer's reagent to give Z. What is Z?

Identify the sets containing correct order against the property mentioned from the following

Observe the following set of reactions
2-Methylpropene $\xrightarrow{\text{HBr}, (\text{CH}_3\text{COO})_2}$ Y
2-Methylpropene $\xrightarrow{\text{HBr}}$ X
Correct statement regarding X and Y is

Which of the following is an example of antifertility drug?

The hormone 'X' increases glucose levels in blood. Low levels of other hormone 'Y' causes lethargyness. What are X, Y respectively?

The catalyst used in the preparation of high density polythene is

Permanganate titrations cannot be performed satisfactorily in presence of HCl. The reason is

The number of non-ionizable valences of Co$^{3+}$ and Pt$^{4+}$ ions in the complexes CoCl$_3\cdot5$NH$_3$ and PtCl$_4\cdot5$NH$_3$ is respectively