question_answer 33)

    Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of, anhydrousandwere 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, where as 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. (a) Only 1                         (b) Only 2                                                (c) 1 and 4                         (d) 2 and 3

Answer:

  (c) As in case of beakers A and 6, heat is given out, so temperature became high, hence it is an exothermic reaction while in beaker C, heat is absorbed from water, so temperature falls, hence it is an endothermic process.