115 g of dry ice (solid CO₂)is dropped into a beaker containing 550 g of 78°C water.The dry ice converts directly to gas,leaving the solution.When the dry ice is gone,the final temperature of the water is 47°C.What is the heat of vaporization of solid CO₂? (c_water = 1.00 cal/g⋅°C)

Question

Quizplus · Accepted Answer

First, we need to calculate the amount of heat absorbed by the water as the dry ice converts to gas: Q = mcΔT = 550 g x 1.00 cal/g⋅°C x (78°C - 47°C) = 17050 cal Next, we can use the heat of vaporization formula to calculate the heat needed to vaporize the dry ice: Q = mL where Q is the heat calculated above, m is the mass of dry ice (115 g), and L is the heat of vaporization we want to find. L = Q/m = 17050 cal / 115 g = 148 cal/g Therefore, the heat of vaporization of solid CO₂ is 148 cal/g, which corresponds to choice D in the answer options.

115 G of Dry Ice (Solid CO2)is Dropped into a Beaker

115 G of Dry Ice (Solid CO₂)is Dropped into a Beaker