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The third ionization enthalpy is minimum for:

a. Mn b. Co c. Ni d. Fe Answer: Consider an element E E2+ → E3+ would be the 3rd I.E. of the element E. Electronic configuration of Mn is... View Article

When gypsum is heated to 393K, it forms:

a. CaSO4. 1/2 H2O b. Dead burnt plaster c. CaSO4 5H2O d. Anhydrous CaSO4 Answer:... View Article

As per Hardy-Schulze formulation, the flocculation values of the following for ferric hydroxide sol are in the order:

a. AlCl3 > K3[Fe(CN)6] > K2CrO4 > KBr = KNO3 b. K3 [Fe(CN)6 ] < K2CrO4 < AlCl3 < KBr < KNO3 c. K3 [Fe(CN)6 ] < K2CrO4... View Article

A graph of vapour pressure and temperature for three different liquids X, Y and Z is shown below:

The following inferences are made: A) X has higher intermolecular interactions compared to Y B) X has lower intermolecular interactions... View Article

The complex that can show fac- and mer-isomers is:

a. [Co(NO2)3(NH3)3] b. [PtCl2(NH3)2 c. [Co(NH3)4Cl2] d. [CoCl2(en)2] Answer: Facial and meridional geometrical isomerism is observed only in... View Article

The stoichiometry and solubility product of a salt with the solubility curve given below is, respectively:

a. X2Y, 2 x 10−9M3 b. XY2, 1 x 10−9M3 c. XY2, 4 x 10−9M3 d. XY, 2 x 10−6M3 Answer: (a) X2Y(s) ⇌ 2X+ + Y2− Ksp = [X+]2[Y2−] = 4 × 10−6 ×... View Article

the first ionization energy of na mg al and si

a. 496, 737, 577, 786 b. 496, 577, 737, 786 c. 496, 577, 786, 737 d. 786, 737, 577, 496 Answer: The expected order is Na < Mg < Al... View Article

For the Balmer series in the spectrum of H-atom, v̅ = R_H [ (1/n₁²) – (1/n₂²)] The correct statements among (A) to (D) are:

A) The integer n1= 2. B) The ionization energy of hydrogen can be calculated from the wave number of these lines. C) The lines of longest... View Article

The predominant intermolecular forces present in ethyl acetate, a liquid, are:

a. London dispersion, dipole-dipole and hydrogen bonding b. hydrogen bonding and London dispersion c. dipole-dipole and hydrogen bonding d.... View Article

The number of bonds between sulphur and oxygen atoms in S₂O₈²⁻ and number of bonds between sulphur and sulphur atoms in rhombic sulphur, respectively, are:

a. 8 and 6 b. 4 and 6 c. 8 and 8 d. 4 and 8 Answer: Here, we have to count S − O single bonds as well as S = O in S2O82–, as each double... View Article

The standard heat of formation (Δ_fH₂₉₈°) of ethane (in kJ/mol), if the heat of combustion of ethane, hydrogen and graphite are -1560, -393.5 and -286 kJ/mol, respectively, is.

Answer: -192.5 kJ/mol C(graphite) + O2(g) → CO2(g) ΔHc°=−286 kJ/mol…………………….(1) H2(g)+ 0.5O2(g)→H2O(l) ΔHc°= −393.5 kJ/mol ………………(2) C2H6(g)... View Article

In the following reactions the sum of the total number of atoms in one molecule of (A),(B) & (C) is

NaCl+K2Cr2O7+ H2SO4 -> (A)+side products (A)+NaOH ->(B)+side products (B)+H2SO4(dil.)+H2O2 ->(C)+side products Answer: 18 (A) = CrO2Cl2,(B)... View Article

The flocculation value of HCl for As₂S₃ sol is 30 m mol L^–1. If H₂SO₄ is used for the flocculation of arsenic sulphide, the amount, in grams, of H₂SO₄ in 250 mL required for the above purpose is

Answer: 0.3675 g For 1L sol 30 mmol of HCl is required. For 1L sol 15 mmol of H2SO4 is required . For 250 mL of sol, (15/4)×98 ×10-3 g of... View Article

3 grams of acetic acid is added to 250 mL of 0.1 M HCl and the solution is made up to 500 mL. To 20 mL of this solution ½ mL of 5 M NaOH is added. The pH of this solution is:

(Given: log 3 = 0.4771, pKa of acetic acid = 4.74, molar mass of acetic acid = 60 g/mole). Answer: 5.22 mmole of acetic acid in 20 mL = 2... View Article

Number of sp² hybrid carbon atoms present in aspartame is

Answer: 9 The marked carbons are sp2 hybridised.... View Article

The ammonia (NH₃) released on quantitative reaction of 0.6 g urea (NH₂CONH₂) with sodium hydroxide (NaOH) can be neutralized by:

a. 200 mL of 0.2 N HCl b. 200 mL of 0.4 N HCl c. 100 mL of 0.1 N HCl d. 100 mL of 0.2 N HCl Answer: d Moles of urea = 0.6/ 60 = 0.01... View Article

Among the following statements A-D, the incorrect ones are:

A. Octahedral Co(III) complexes with strong field ligands have high magnetic moments B. When Δo < P, the d- electron configuration of Co(III)... View Article

Within each pair of elements F & Cl, S & Se and Li & Na, respectively, the elements that release more energy upon an electron gain are:

a. Cl, Se and Na b. Cl, S and Li c. F, S and Li d. F, Se and Na Answer: b Element First Electron gain enthalpy(kJ/mol)... View Article

What is the rate expression for the reverse reaction

2H2(g) + 2NO(g) -> N2(g) + 2H2O(g) The observed rate expression is, rate = kf[NO]2[H2]. a. kb[N2][H2O]2 b. kb[N2][H2O] c. kb[N2][H2O]2/[H2]... View Article

Identify the correct labels of A, B and C in the following graph from the options given below:

Root mean square speed (Vrms); most probable speed (Vmps); average speed (Vav) a. A = Vmps, B = Vav, C = Vrms b. A = Vmps, B = Vrms, C = Vav... 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	28	29	30	31