List of top Chemistry Questions

Marsh gas mainly contains
For decolourisation of $1$ mole of acidified $KMnO_4$ the moles of $H_2O_2$ required are
Lanthanoid contraction is caused due to
The noble gas forming maximum number of compounds is
Which of the following is soluble in water?
Which of the following will decolourise alkaline $KMnO_4$ solution?
2.76 g of silver carbonate on being strongly heated yields a residue weighing
The largest number of molecules is in
The total number of electrons in one molecule of carbon dioxide is
When the same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide, the ratio of volumes of hydrogen evolved is
The compound which contains both ionic and covalent bonds is
The temporary hardness of water is due to calcium bicarbonate can be removed by adding
Ammonia gas can be dried by

Preparation of ethers by acid dehydration of secondary or tertiary alcohols is not a suitable method. Give reason.

The reaction CH3CH2I + KOH(aq) \(\rightarrow\) CH3CH2OH + KI is classified as 

Draw the Lewis structures for the following molecules and ions: \(H_2S\), \(SiCl_4\), \(BeF_2\), \(CO_3^{2-}\) , \(HCOOH\)

The correct decreasing order of boiling point of hydrogen halides is
The following results are observed when sodium metal is irradiated with different wavelengths. Calculate (a) threshold wavelength and, (b) Planck’s constant
λ (nm)500 450400 
v × 10–5(cm s–1)2.554.355.35

What is the coordination entity formed when excess of aqueous \(KCN\) is added to an aqueous solution of copper sulphate? Why is it that no precipitate of copper sulphide is obtained when \(H_2S(g)\) is passed through this solution?

The ionisation potential is lowest for the

Draw the structures of all isomeric alcohols of molecular formula C5H12O and give their IUPAC names. (ii)Classify the isomers of alcohols in question 11.3(i)as primary, secondary and tertiary alcohols.

$ {{(C{{H}_{3}})}_{3}}CMgCl $ on reaction with $ {{D}_{2}}O $ produces
What do you understand by isoelectronic species? Name a species that will be isoelectronic with each of the following atoms or ions. 
  1. F- 
  2. Ar 
  3. Mg2+ 
  4. Rb+
(B) (a) Write chemical equations of the following reactions: (i) Phenol is treated with conc. \( HNO_3 \).
(ii) Propene is treated with \( B_2H_6 \) followed by oxidation by \( H_2O_2 / OH^- \).
(iii) Sodium t-butoxide is treated with \( CH_3Cl \).
Bromine monochloride, BrCl decomposes into bromine and chlorine and reaches the equilibrium:
\(2BrCl (g) ⇋ Br_2 (g) + Cl_2 (g)\)
for which Kc = 32 at 500 K. If initially pure BrCl is present at a concentration of 3.3 × 10–3 mol L–1, what is its molar concentration in the mixture at equilibrium?