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which of the following compound has highest rate of decarboxylation (a) CH3COOH (b) C6H5COOH (c) C6H5CH2COOH (d) CH3COCH2COOH

Solution: (D) CH3COCH2COOH is a β-keto acid. β-keto acid is a molecule in containing a ketone on the β-carbonof a carboxylic acid.... View Article

When copper sulphate dissolves in the ammonium hydroxide one deep blue complex is formed. what is the co-ordination no of copper in this complex?

The complex's coordination number [Cu(NH3)4] SO4 is a four-letter word. The complex's geometry was formed. The metal ions will be perturbed to... View Article

Assertion (a) helium is used in diving apparatus. reason (r) helium is very less soluble in blood.

In diving apparatus, a combination of 2% O2 and 98 percent He is utilised to achieve the same partial pressure of O2 as regular air at 1 atm. N2... View Article

If ΔH is the change in enthalpy and ΔE the change in internal energy accompanying a gaseous reaction?

ΔH = ΔE+Δ(PV)ΔH = ΔE+Δ(nRT)When number of moles in product is less than number of moles in reactant.Δn... View Article

ph of a weak acid is 4 it is diluted by 100 times

If pH is initially 4 and the solution is diluted by 100 times, the concentration of hydrogen ions gets divided by 100 i.e when we calculate pH,... View Article

At certain temperature the value of pkw is 13.4 the measured ph of a solution at same temperature is 7. The solution is

Kw = [H+][OH−] = 13.4In neutral water, [H+] = [OH−]If we calculated the pH of H2O from the above value, it come to be 6.7So, the... View Article

The specific rate constant of a first order reaction depends on the (a)concentration of the reactant (b)concentration of the product (c) time (d)temperature

The correct answer is (d) temperature First-order reaction A first-order reaction can be defined as a chemical reaction in which the reaction... View Article

Vapour density of a metal chloride is 66. Its oxide contains 53% metal. The atomic weight of the metal is

Calculation of Equivalent weight of metal:Let the weight of metal oxide to be 100 g.weight of metal = 53 g weight of oxygen = 47 g.Now, as we all... View Article

Non-metals react with oxygen to form _ or __.

Non-metals react with oxygen to form acidic oxides or neutral oxides. C(s) + O2(g) --> CO2(g) Carbon + Oxygen --> Carbon dioxide... View Article

Four monobasic acids a, b, c and d have the values as – 11.5, –7.5, –12.4 and – 8.9 kcal/mol. when they are neutralized by a common base the acidic character or base the order

The enthalpy of neutralization is the change in enthalpy that occurs when one equivalent of an acid and one equivalent of a base undergo a... View Article

if successive ionisation energies of an element are 7.9 ev, 13.2 ev and 247.8 ev respectively, the element is expected to be

The ion must invest a lot of energy (247.8 eV) to release the third electron after releasing two electrons in a row. This indicates that the ion... View Article

a compound with empirical formula xy2, has the vapour density equal to its empirical formula weight, its molecular formula is

The empirical formula for a compound of X and Y is XY2. It has the same vapour density as its empirical formula weight. The molecular weight is... View Article

Each of the following ion contains vanadium in +5 oxidation state except:Each of the following ion contains vanadium in +5 oxidation state except: VO+2, V(OH)+4, VO2+, [VO3OH]2−

VO2+, V(OH)4+, VO2+, [VO3OH]2− Answer In VO2+, the oxidation state of vanadium is +4. In all other complexes, it is +5.... View Article

Basicity increases down the group

As the atomic radius lowers, the ionisation energy decreases, implying that the tendency to lose electrons increases, implying an increase in... View Article

Assertion: All homogenous substances are pure. Reason: Alloys are homogeneous mixtures of solids. A. Both assertion and reason are correct and reason is the correct explanation for assertion. B. Both assertion and reason are correct but reason is not the correct explanation for assertion. C. Assertion is correct but reason is incorrect D. Assertion is incorrect but reason is correct

Alloys are discovered to be homogenous mixes of two or more metals. However, just because an alloy is homogeneous doesn't mean it has to be... View Article

The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from avolume of 10dm^3 to a volume of 100 dm^3 at 27^0C is

Entropy change for an isothermal process isΔS = 2.303Rlog(V2/V1)ΔS = 2.303×2×8.314×log(100/10)=38.294J/mol/K... View Article

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