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Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous CuSO4 and NaCl were added to the beakers A, B and

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प्रश्न

Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous CuSOand NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is(are) correct?

  1.  In beakers A and B, exothermic process has occurred.
  2. In beakers A and B, endothermic process has occurred.
  3. In beaker C exothermic process has occurred.
  4.  In beaker C endothermic process has occurred.

विकल्प

  • (i) only

  •  (ii) only

  • (i) and (iv)

  •  (ii) and (iii)

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उत्तर

(i) and (iv)

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अध्याय 1: Chemical Reactions and Equations - Exemplar [पृष्ठ २]

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एनसीईआरटी एक्झांप्लर Science Exemplar Class 10
अध्याय 1 Chemical Reactions and Equations
Exemplar | Q 5. | पृष्ठ २

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