Answer:
c) (12×0.9889) + (13×0.01108)
Explanation:
Given data:
Percentage of C-12 = 98.89%
Percentage of C-13 = 1.108%
Atomic mass = ?
Solution:
98.89/100 = 0.9889
1.108/ 100 = 0.01108
Atomic mass = (12×0.9889) + (13×0.01108)
Atomic mass = (11.8668 + 0.144034)
Atomic mass = 12.01084
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.
Sugar. (We need a design tech section)
