Answer is in the photo. I can't attach it here, but I uploaded it to a file hosting. link below! Good Luck!
tinyurl.com/wpazsebu
Answer:
31.24 kJ
Explanation:
- SiO₂(g) + 3C(s) → SiC(s) + 2CO(g) ΔH° = 624.7 kJ/mol
First we <u>convert 3.00 grams of SiO₂ to moles</u>, using its <em>molar mass</em>:
- 3.00 g SiO₂ ÷ 60.08 g/mol = 0.05 mol
Now we <u>calculate the heat absorbed</u>, using the <em>given ΔH°</em>:
If the complete reaction of 1 mol of SiO₂ absorbs 624.7 kJ, then with 0.05 mol:
- 0.05 mol * 624.7 kJ/mol = 31.24 kJ of heat would be absorbed.
Answer:
C: The temperature of the substance increases as it sits in the beaker of water
Explanation:
This question was taken from a video where an attempt was made to investigate the changes in temperature when a substance undergoes change from it's solid phase to its liquid phase.
To do this, as seen in the video online, it shows a solid substance in a test tube being placed in a beaker of water.
From observation, the water in the beaker has a warmer temperature than the solid substance present in the test tube and this in turn makes the test tube gradually increase in temperature.
Thus, the solid substance will as well increase increase in temperature when it is placed in the beaker of water.