JEE Main questions
34495 published questions with worked solutions.
- Given below are two statements: Statement (I): Potassium hydrogen phthalate is a primary standard for standardisation of sodium...
- Ionic reactions with organic compounds proceed through (A) Homolytic bond cleavage (B) Heterolytic bond cleavage (C) Free radical...
- K_a for CH_3COOH is 1.8 × 10^ -5 and K_b for NH_4OH is 1.8 × 10^ -5 . The pH of ammonium acetate solution will be ______.
- Among the following oxides of p-block elements, number of oxides having amphoteric nature is ________. Cl_2O_7, CO, PbO_2, N_2O,...
- The lowest oxidation number of an atom in a compound A_2B is –2. The number of electrons in its valence shell is _______.
- Number of optical isomers possible for 2- chlorobutane _______.
- Consider the following reaction: 3PbCl_2 + 2(NH_4)_3PO_4 → Pb_3(PO_4)_2 + 6NH_4Cl. If 72 mmol of PbCl_2 is mixed with 50 mmol of...
- The number of white coloured salts, among the following is _______. (a) SrSO_4 (b) Mg(NH_4)PO_4 (c) BaCrO_4 (d) Mn(OH)_2 (e)...
- Total number of deactivating groups in aromatic electrophilic substitution reaction among the following is _______. (a) –COOCH_3...
- The number of molecules/ions having trigonal bipyramidal shape is _______. PF_5, BrF_5, PCl_5, [PtCl_4]^ 2- , BF_3, Fe(CO)_5
- The potential for the given half cell at 298 K is (–) ________ × 10^ -2 V. 2H^+(aq) + 2e^- → H_2(g), [H^+] = 1M, P_ H_2 = 2 atm...
- Let S = z ∈ C : |z − 1| = 1 and ( 2 - 1)(z + z) - i(z - z) = 2 2 . Let z_1, z_2 ∈ S be such that |z_1| = _ z S |z| and |z_2| = _...
- Let x^2 a^2 + y^2 b^2 = 1, a > b be an ellipse, whose eccentricity is 1 2 and the length of the latusrectum is 14 . Then the...
- For 0 < θ < π/2, if the eccentricity of the hyperbola x^2 - y^2 ^2 = 5 is 7 times eccentricity of the ellipse x^2 ^2 + y^2 = 5,...
- Let f : R → R and g : R → R be defined as f(x) = cases _e x, & x > 0 e^ -x , & x 0 cases and g(x) = cases x, & x 0 e^x, & x < 0...
- Let the median and the mean deviation about the median of 7 observation 170, 125, 230, 190, 210, a, b be 170 and 205 7...
- If n is the number of ways five different employees can sit into four indistinguishable offices where any office may have any...
- If the system of equations 2x + 3y − z = 5, x + αy + 3z = −4, 3x − y + βz = 7 has infinitely many solutions, then 13αβ is equal...
- A bag contains 8 balls, whose colours are either white or black. 4 balls are drawn at random without replacement and it was found...
- The value of the integral _0^ /4 x ,dx ^4(2x) + ^4(2x) equals: