MCQ
The valency shell of calcium contains
- A$8$ electrons
- B$6$ electrons
- C$4$ electrons
- ✓$2$ electrons
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$C{H_4}(g) + 2{O_2}(g) \to C{O_2}(g) + 2{H_ {2}}O(l);$
$\Delta H = - 890.3\,kJ$
How many grams of methane would be required to produce $445.15\, kJ$ of heat of combustion.....$g$

