NEET 2019 · ChemistryPrevious Year Question

Under isothermal condition, a gas at $300 K$ expands from $0.1 L$ to $0.25 L$ against a constant external pressure of $2 bar$ . The work done by the gas is (Given that $1 L bar = 100 J$ )

Answer: (A) $- 30 J$ . \textbf{Answer:} (A) $- 30 J$ \textbf{Solution:} Work done against a constant external pressure: $w = - p_{e x t} Δ V = - 2 bar \times (0.25 - 0.10) L = - 0.30 L bar$ .

A. $- 30 J$ ✓
B. $5 kJ$
C. $25 J$
D. $30 J$

Correct Answer

(A) $- 30 J$

Solution & Explanation

\textbf{Answer:} (A) $- 30 J$ \textbf{Solution:} Work done against a constant external pressure: $w = - p_{e x t} Δ V = - 2 bar \times (0.25 - 0.10) L = - 0.30 L bar$ . Converting with $1 L bar = 100 J$ : $w = - 0.30 \times 100 = - 30 J$ . The negative sign confirms work is done by the gas on expansion. Mapped: source numeric key "1" $= - 30 J$ → option A.

🎯

43,000+ questions in हिंदी & English · one-tap toggle

Practice NEET 2019 Chemistry — free, with instant solutions

43,000+ NEET questions solved step-by-step, chapter-wise, in the MedicNEET app.

Open →📚Practice all NEET Chemistry PYQs chapter-wise →💡Don't get it? Learn the Thermodynamics concepts →

← Chemistry Q26 Chemistry Q28 →

More NEET PYQ solutions

ChemIdentify the suitable reagent for the following conversion: C6H5COOCH3 -> C6H5CHO (methyl benzoate to benzaldehyde)ChemThe correct order of decreasing acidity of the following aliphatic acids is ChemThe major product of the following reaction is: 4-oxo-4-phenylbutanenitrile C6H5-CO-CH2-CH2-CN is treated with (i) CH3MgBr (excess) and then (ii) H3O+.ChemOut of the following complex compounds, which compound will have the minimum conductance in solution?ChemWhich of the following are paramagnetic? A. [NiCl4]^2- B. Ni(CO)4 C. [Ni(CN)4]^2- D. [Ni(H2O)6]^2+ E. Ni(PPh3)4 ChemThe correct order of the wavelength of light absorbed by the following complexes is: A. [Co(NH3)6]^3+ B. [Co(CN)6]^3- C. [Cu(H2O)4]^2+ D. [Ti(H2O)6]^3+ChemThe correct order of decreasing basic strength of the given amines is: (N-ethylethanamine = (C2H5)2NH; ethanamine = C2H5NH2; N-methylaniline = C6H5NH(CH3); benzenamine/aniline = C6H5NH2)ChemPredict the major product P in the following sequence of reactions. The starting material is 1-methylcyclopent-1-ene: (i) HBr, benzoyl peroxide; (ii) KCN; (iii) Na(Hg)/C2H5OH P (major). The structures of the options (A)-(D) are shown in the image below:

More: All NEET 2019 Chemistry PYQs · NEET Chemistry PYQs · All NEET PYQs · Previous year papers

Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is (Given that 1 Lbar=100 J)

Solution & Explanation

More NEET PYQ solutions

Under isothermal condition, a gas at $300 K$ expands from $0.1 L$ to $0.25 L$ against a constant external pressure of $2 bar$ . The work done by the gas is (Given that $1 L bar = 100 J$ )