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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. London... 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... 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) + 3.5O2(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) = Na2CrO4 and (C)... 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... 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:... View Article

Number of sp² hybrid carbon atoms present in aspartame is

Answer: 9 The marked carbons are sp2 hybridised.

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... 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... 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... 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.... 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... View Article

The redox reaction among the following is:

a. formation of ozone from atmospheric oxygen in the presence of sunlight b. reaction of H2SO4 with NaOH c. combination... View Article

Among statements I-IV, the correct ones are:

I. Decomposition of hydrogen peroxide gives dioxygen II. Like hydrogen peroxide, compounds, such as KClO3, Pb(NO3)2 and NaNO3 when heated... View Article

The refining method used when the metal and the impurities have low and high melting temperatures, respectively, is:

a. vapour phase refining b. distillation c. liquation d. zone refining Answer: c Liquation is the process of refining a... View Article

Two open beakers one containing a solvent and the other containing a mixture of that solvent with a non-volatile solute are together sealed in a container. Over time:

a. the volume of the solution and the solvent does not change b. the volume of the solution increases and... View Article

The number of possible optical isomers for the complexes [MA₂ B₂] with sp³or dsp² hybridized metal atom, respectively, is:

Note: A and B are unidentate neutral and unidentate monoanionic ligands, respectively. a. 0 and 1 b. 0 and 0... View Article

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