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The rate equation for the reaction A + B → P is rate = k[A]½ [B]2. What is the order of reaction

Solution: (2.5) For A + B → P r = k[A]½ [B]2 The order of the reaction = 2 + 1/2 = 5/2 = 2.5... View Article

When Mn(OH)2 is made by adding an alkali to a solution containing Mn2+ ions, the precipitate quickly darkens, and eventually goes black. What might be the chemical giving black colour

A. Mn2O3 B. MnO2 C. Mn2O5 D. None of these Solution: (B) Mn(OH)2 is oxidized by oxygen in the air to form MnO2 which eventually goes black.... View Article

Among the following compounds, the number of compounds that do not produce acidic or basic solutions when dissolved in water is

NaCl, BeCl2, BaCl2, Li2O, MgO, CaH2, CaSO4. Solution: (3) The compounds are; Magnesium Oxide (MgO) will react with water to form Magnesium... View Article

For the cell reaction: 4Br− + O2 + 4H+ ⇌ 2Br2 + 2H2O; E∘ = 0.18V. The value of (log KC) at 298 K is [2.303 RT / F = 0.06]

A. 12 B. 6 C. 18 D. 3 Solution: (A) From the question; E0 = 0.18V 2.303RT/F = 0.06 Cell reaction: 4Br− + O2 + 4H+ ⇌ 2Br2 + 2H2O Let us... View Article

The ratio of (E2 − E1) to (E4 − E3) for the hydrogen atom is approximately equal to

A. 10 B. 15 C. 17 D. 12 Solution: (B) In hydrogen atom formula for energy is E = −13.6 × z2 / n2, Where, z = Atomic number, n = Principle... View Article

What is common between P4O6 and P4O10?

A. sp3 hybridized B. p – o – p bond C. Acidic Oxide D. All of these Solution: (D) The common features of P4O6 and P4O10: - Both have closed... View Article

The unit cell of aluminium is a cube with an edge length of 405 pm. The density of aluminium is 2.70 g cm−3. What is the structure of the unit cell of aluminium

A. Body-centered cubic cell B. Face-centred cubic cell C. End-centered cubic cell D. Simple cubic cell Solution: (B) Density of crystal, ρ =... View Article

In Kjeldahl’s method, ammonia from 5 g of good neutralizes 30 cm2 of 0.1 N acid. The percentage of nitrogen in the food is

A. 0.84 B. 8.4 C. 16.8 D. 1.68 Solution: (A) From Kjeldahl's method, the percentage of nitrogen = 1.0 × N × V / w = 1.4 × 0.1 × 30 / 5 = 0.84%... View Article

1 M NaOH solution was slowly added into 1000 mL of 183.75 g impure H2SO4 solution and the following plot was obtained

A. 75%, −⅓ B. 80%, −½ C. 80%, −1 D. None of these Solution: (C) Let us do the calculation below. Moles of NaOH consumed when reacted with... View Article

Which one of the following groupings represents a collection of isoelectronic species? (At. nos.: Cs = 55, Br = 35)

A. Na+, Ca2+, Mg2+ B. N3–, F–, Na+ C. Be, Al3+, Cl– D. Ca2+, Cs+, Br. Solution: (B) If we define isoelectronic species these are species... View Article

The correct IUPAC name of BR is

A. 7-Bromo-2Z, 5E-Heptadiene B. 1-Bromo-2Z, 5E-Heptadiene C. 1-Bromo-2Z, 5Z-Heptadiene D. 1-Bromo-2E, 5Z-Heptadiene Solution: (D) The... View Article

The litmus solution when shaken with charcoal becomes colourless. Explain

Solution: If we take a solution of acetic acid in water and shake it in the presence of charcoal, a part of the acid is adsorbed by the... View Article

Volume of O2 liberated at STP by 100 ml of 10 volume H2O2 solution is

Solution: (1000) Given, Volume of H2O2 = 100 ml Volume strength of H2O2 = 10 volume We can calculate the volume of O2 produced at STP by the... View Article

The pressure of sodium vapour in a 1.0 L container is 10 torr at 1000 oC. How many atoms are in the container

A. 9.7 × 1017 B. 7.6 × 1019 C. 4.2 × 1017 D. 9.7 × 1019 Solution: (B) 10 torr = 0.0013 × 10 atm = 0.013 atm By ideal gas equation, n = PV... View Article

The precipitate of Ag2CrO4 (Ksp = 1.9 x 10-12) is obtained when equal volumes of the following are mixed

A. 10-4 MAg+ + 10-4 MCrO42- B. 10-2 MAg+ + 10-5 MCrO42- C. 10-5 MAg+ + 10-3 MCrO42- D. 10-4 MAg+ + 10-5 MCrO42- Solution: (B) Precipitation... View Article

Bond order normally gives an idea of the stability of a molecular species. All the molecules viz. H2, Li2 and B2 have the same bond order yet they are not equally stable. Their stability order is:

A. H2 > B2 > Li2 B. H2 > Li2 > B2 C. Li2 > B2 > H2 D. B2 > H2 > Li2 Solution: (A) The configuration of the three... View Article

M	T	W	T	F	S	S
	1	2	3	4	5	6
7	8	9	10	11	12	13
14	15	16	17	18	19	20
21	22	23	24	25	26	27
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