Question

A reaction vessel inside a calorimeter contains 150 g of water at 19°C. A reaction takes place in this chamber, after the reaction is complete, the temperature of water is 29°C. How many Joules were released/absorbed during this reaction?

a) 15,000 J absorbed
b) 15,000 J released
c) 30,000 J absorbed
d) 30,000 J released

Answer 1

The amount of heat released or absorbed during a reaction can be calculated using the equation q = mcΔT, where q is the amount of heat, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature. In this case, 15,000 J of heat was released during the reaction. Correct option is b)

Step-by-step explanation:

The heat released or absorbed during a chemical reaction can be calculated using the heat capacity and change in temperature of the system. In this case, we have 150 g of water at 19°C that reacts and reaches a final temperature of 29°C. To calculate the amount of heat released or absorbed, we can use the equation q = mcΔT, where q is the amount of heat, m is the mass of the water, c is the specific heat capacity of water, and ΔT is the change in temperature. The specific heat capacity of water is approximately 4.18 J/g°C. Plugging in the values, we can calculate the amount of heat:

q = (150 g)(4.18 J/g°C)(29°C - 19°C) = 1500 J

Therefore, the correct answer is b) 15,000 J released.