List of top Chemistry Questions

Assertion (A): The boiling point of ethanol is higher than that of methoxymethane.
Reason (R): There is intramolecular hydrogen bonding in ethanol.

Assertion (A): The boiling points of alkyl halides decrease in the order: RI>RBr>RCl>RF.
Reason (R): The boiling points of alkyl chlorides, bromides and iodides are considerably higher than that of the hydrocarbon of comparable molecular mass.

An unripe mango placed in a concentrated salt solution to prepare pickle, shrivels because __________

Which of the following statements is not true about glucose?

The best reagent for converting propanamide into propanamine is:

The acid formed when propyl magnesium bromide is treated with CO_2 followed by acid hydrolysis is:

Which is the correct order of acid strength from the following?

Consider the following compounds:
(i) CH₃CH₂Br
(ii) CH₃CH₂CH₂Br
(iii) CH₃CH₂CH₂CH₂Br
Arrange the compounds in the increasing order of their boiling points.

Which of the following are paramagnetic?
A. [NiCl$_4$]$^{2-}$
B. Ni(CO)$_4$
C. [Ni(CN)$_4$]$^{2-}$
D. [Ni(H$_2$O)$_6$]$^{2+}$
E. Ni(PPh$_3$)$_4$
Choose the correct answer from the options given below:

Given below are two statements:
Statement I: Benzendiazonium salt is prepared by the reaction of aniline with nitrous acid at 273-278 K. It decomposes easily in the dry state.
Statement II: Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzendiazonium salt with KI.
In the light of the above statements, choose the most appropriate answer from the options given below:

Consider the following compounds: K$_2$O$_2$, H$_2$O$_2$, and H$_2$SO$_4$
The oxidation states of the underlined elements in them are, respectively:

Which one of the following compounds does not decolorize bromine water?

C(s) + 2H$_2$(g) $\rightarrow$ CH$_4$(g); $\Delta H = -74.8 \, \text{kJ mol}^{-1}$
Which of the following diagrams gives an accurate representation of the above reaction?

5 moles of liquid X and 10 moles of liquid Y make a solution having a vapor pressure of 70 torr. The vapor pressures of pure X and Y are 63 torr and 78 torr, respectively. Which of the following is true regarding the described solution?

Which among the following electronic configurations belong to main group elements?
A. [Ne]3s$^1$
B. [Ar]3d$^3$4s$^2$
C. [Kr]4d$^5$3s$^2$5p$^5$
D. [Ar]3d$^10$4s$^1$
E. [Rn]5f$^7$6d$^2$7s$^2$
Choose the correct answer from the options given below:

If the rate constant of a reaction is 0.03 s$^{-1}$, how much time does it take for a 7.2 mol L$^{-1}$ concentration of the reactant to get reduced to 0.9 mol L$^{-1}$?
(Given: log 2 = 0.301)

Match List I with List II:

Choose the correct answer from the options given below:

Identify the correct orders against the property mentioned:
A. H$_2$O $>$ NH$_3$ $>$ CHCl$_3$ - dipole moment
B. XeF$_4$ $>$ XeO$_3$ $>$ XeF$_2$ - number of lone pairs on central atom
C. O–H $>$ C–H $>$ N–O - bond length
D. N$_2$>O$_2$>H$_2$ - bond enthalpy
Choose the correct answer from the options given below:

The correct order of the wavelength of light absorbed by the following complexes is:
A. $[ \text{Co(NH}_3\text{)}_6]^{3+}$
B. $[ \text{Co(CN)}_6]^{3-}$
C. $[ \text{Cu(H}_2\text{O)}_4]^{2+}$
D. $[ \text{Ti(H}_2\text{O)}_6]^{3+}$
Choose the correct answer from the options given below:

The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes n = 2 $\rightarrow$ n = 3 and n = 4 $\rightarrow$ n = 6 transitions, respectively, is:

Match List I with List II:

Choose the correct answer from the options given below:

Higher yield of NO in the reaction
N$_2$ (g) + O$_2$ (g) $\rightarrow$ 2NO (g)
can be obtained at [$\Delta H$ of the reaction = +180.7 kJ mol$^{-1}$]

Which of the following aqueous solutions will exhibit the highest boiling point?

If the half-life ($t_{1/2}$) for a first-order reaction is 1 minute, then the time required for 99.9% completion of the reaction is closest to:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): I$^-$ undergoes SN$_2$ reaction faster than Cl$^-$.
Reason (R): Iodine is a better leaving group because of its large size.
In the light of the above statements, choose the correct answer from the options given below: