JEE Main 2019 — Chemistry Physical Chemistry
The entropy change associated with the conversion of 1kg of ice at 273K to water vapours at 383K is:
(Specific heat of water liquid and water vapour are 4.2kJK− and 2.0kJK−1kg−1 ; heat of liquid fusion and vaporization of water are 334kJkg−1 and 2491kJkg−1 , respectively). ( log 273=2.436,log373=2.572,log383=2.583 )
Held on 9 Jan 2019 · Verified 6 Jul 2026.
9.26kJkg−1K−1
2.64kJkg−1K−1
8.49kJkg−1K−1
7.90kJkg−1K−1
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What is the ratio of wave number of first line (lowest energy line) of Balmer series of H atomic spectrum to first line of its Brackett series?
  Which of the following point in Figure 2 most accurately represents the nodal surface as shown in Figure 1?
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