HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

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A gas is allowed to expand in a well-insulated container against a constant external pressure of 2.5 bar from an initial volume of 2.5 L to a final volume of 4.5 L. The change in internal energy, ΔU of the gas will be _______.

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6.24 g of ethanol are vaporized by supplying 5.89 kJ of heat. Enthalpy of vaporization of ethanol will be _______.

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Which of the following are not state functions?

1. Q + W
2. Q
3. W
4. H - TS

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For vaporization of water at 1 bar, ΔH = 40.63 kJ mol^–1 and ΔS = 108.8 J K^–1 mol^–1 . At what temperature, ΔG = 0?

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The rate law for the reaction aA + bB → P is rate = k[A] [B]. The rate of reaction doubles if _________.

Answer the following in one or two sentences.

For the reaction,

\[\ce{N2_{(g)} + 3H2_{(g)} -> 2NH3_{(g)}}\],

what is the relationship among `("d"["N"_2])/"dt"`, `("d"["H"_2])/"dt"` and `("d"["NH"_3])/"dt"`?

Answer the following in brief.

How instantaneous rate of reaction is determined?

Which of the following has the highest electron gain enthalpy?

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Hydrides of group 16 are weakly acidic. The correct order of acidity is ______.

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Which of the following element does not show an oxidation state of +4?

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HI acid when heated with conc. H₂SO₄ forms _______.

Which of the following occurs in a liquid state at room temperature?

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In pyrosulfuric acid oxidation state of sulfur is _______.

The correct order of increasing reactivity of C-X bond towards nucleophile in the following compounds is:

(I)

(II)

(III) (CH₃)₃ C-X

(IV) (CH₃)₂ CH-X

\[\ce{CH3 - CH = CH2 ->[HI][Peroxide]}\]

The major product of the above reaction is,

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The best method for the preparation of alkyl fluorides is _______.

Butanenitrile may be prepared by heating ______.

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Choose the compound from the following that will react fastest by S_N1 mechanism

The product ‘B’ in the above reaction sequence is,

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Which of the following is likely to undergo racemization during alkaline hydrolysis?

(I)

\[\begin{array}{cc}
\ce{CH3-CH-C2H5}\\
|\\
\ce{Cl}\end{array}\]

(II)

(III) 

(IV)

\[\begin{array}{cc}
\ce{\phantom{.......}CH3}\\
\phantom{.....}|\\
\ce{CH3-CH}\\
\phantom{.....}|\\
\ce{\phantom{..........}CH2Cl}
\end{array}\]