Question

When 600 mL of 0.2 M HNO₃ is mixed with 400 mL of 0.1M NaOH solution in a flask, the rise in temperature of the flask is ____ x 10^{-2 0}C. (Enthalpy of neutralisation = 57 kJ mo1^-1 and Specific heat of water = 4.2 JK^-1 g^-1) (Neglect heat capacity of flask)

Answer 1

Answer mentioned as 54 (Closest integer)

Comments

Why the mass of water is taken as 1000ml×1g/ml, why not find mass from 40 mili mole×18(molar mass)?

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Here we consider the whole mass of water (solution) (600 mL from HNO3 & 400 mL from NaOH solution) because 2280J energy increase the temperature of whole solution not only 40 m mole water.