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 C respectively. It was observed that there was an increase in the temperature of the solution 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?(i) In beakers A and B, exothermic process has occurred.
(ii) In beakers A and B, endothermic process has occuBftd.
(iii) In beaker C exothermic process has occurred.
(iv) In beaker C endothermic process has occurred.

(a)(i) only

(b) (ii) only

(c) (i) and (iv)

(d)(iv) AcademicChemistryNCERTClass 10 Correct answer: (c) (i) and (iv) Explanation: The reaction taking place in beaker A: $NaOH + H_2O → Na^+ + OH^− + H_2O + heat $ The reaction taking place in beaker B: $CuSO_4(s) + 5H_2O(l) → CuSO_4.5H_2O(s) + heat$ Therefore, both A and B  are exothermic reactions that are taking place resulting in rise in temperature.  On the other hand in beaker C, an endothermic reaction is taking place as heat is being absorbed, resulting in a decrease in temperature. $NaCl + H_2O + heat→Na^+ + Cl^− + H_2O$ Tutorialspoint Simply Easy Learning Updated on: 10-Oct-2022 44 Views Related Articles Three beakers labeled 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 C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas, in the case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is (are) correct?In beakers A and B, the exothermic process has occurred.In beakers A and B, the endothermic process has occurred.In beaker C exothermic process has occurred.In beaker C endothermic process has occurred.(a) (i) only(b) (ii) only(c) (i) and (iv)(d) (ii) and (iii) Three beakers labelled as A, B, and C each containing 25 mL of water were taken. A small amount of NaOH, and. CuSO4 and 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 the case of beaker C, the temperature of the solution falls. Which one of the following statements is/are correct?In beakers A and B, an exothermic process has occurred.In beakers A and B, an endothermic process has occurred.In beaker C, the exothermic process has occurred.In beaker C, an endothermic process has occurred.Only IOnly III and IVII and III Paheli prepared a blue coloured solution of copper sulphate in beaker A and placed an iron nail in it. Boojho prepared a yellowish-green solution of ferrous sulphate in beaker B and placed a copper wire in it. What changes will they observe in the two beakers after an hour? Which of the following is (are) an endothermic process(es)?Dilution of sulphuric acidSublimation of dry iceCondensation of water vapoursEvaporation of water(a) (i) and (iii)(b) (ii) only(c) (iii) only (d) (ii) and (iv) The teacher instructed three students ‘A’, ‘B’ and ‘C’ respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). ‘A’ dissolved 50g of NaOH in 100 mL of water, ‘B’ dissolved 50g of NaOH in 100g of water while ‘C’ dissolved 50g of NaOH in water to make 100 mL of solution. Which one of them has made the desired solution and why? Seema takes three beakers A, B and C filled with aqueous solution of glucose, alcohol and hydrochloric acid respectively as shown in the following figure:(i) State your observation in terms of glowing of bulb when the switch is ON.(ii) Justify your observations by giving reason for each case. (iii) Mention the change noticed with appropriate reason if the content of beaker B is replaced by NaOH solution." 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The metal could beAlAuCuPt The process of respiration is:(a) an oxidation reaction which is endothermic(b) a reduction reaction which is exothermic(c) a combination reaction which is endothermic(d) an oxidation reaction which is exothermic (a) What do you understand by exothermic and endothermic reactions?(b) Give one example of an exothermic reaction and one of an endothermic reaction.(c) Which of the following are endothermic reactions and which are exothermic reactions?    (i) Burning of natural gas   (ii) Photosynthesis   (iii) Electrolysis of water    (iv) Respiration   (v) Decomposition of calcium carbonate What happens when a solution of an acid is mixed with a solution of a base in a test tube?The temperature of the solution increasesThe temperature of the solution decreasesThe temperature of the solution remains the sameSalt formation takes place(a) (i) only(b) (i) and (iii)(c) (ii) and (iii)(d) (i) and (iv) What happens when a solution of an acid is mixed with a solution of a base in a test tube?(i) Temperature of the solution decreases(ii) Temperature of the solution increases (iii) Temperature of the solution remains the same(iv) Salt formation takes place(a) (i) and (iv)    (b) (i) and (ii) (c) (ii) only     (d) (i) and (iv) A student prepared 20% sodium hydroxide solution in a beaker containing water. 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