Answer to Question #91194 in General Chemistry for Steven Maquiling

Question

acetylen,c2h2 is used in weldng torches. It releases a lot of energy when burned in oxygen. One gram of acetylene releases 48.2kJ. When 0.75g of acetylene is burned in a bomb calorimeter (heat capacity=1.117kJ/°C), the final temperaturre of the bomb is 54.5°C. What is the initial temperature of the calorimeter? (Pls provide solutions) Thank you

Answer 1

Solution.

If during the burning of 1 gram of acetylene 48.2 kJ is released, then during the burning of 0.75 grams it is released:

$$Q = \frac{0.75 \times 48.2}{1}$$

Q = 36.15 kJ

$$Q = q \times \Delta t$$

q = 1.117 kJ/°C

$$\Delta t = \frac{Q}{q}$$ $$\Delta t = t2-t1$$ $$\Delta t = \frac{36.15}{1.117}$$

$$\Delta t = 32.36$$

$$t1 = t2 - \Delta t$$

t1 = 22.14 °C

Answer:

t1 = 22.14 °C