Because they follow the octet rule and the outer most electrons, the valence electron shell is full.
It would be C, 6.2 x 10^23.
Avogadro's number, or, the mole, is 6.02 x 10^23. Although the grams and molar mass of an element may be different, every element must have the same amount of atoms to obey avogadro's number.
Aluminum, silicon, potassium and oxygen.
In the combustion process using excess oxygen, each mole of methane results to 1 mole of co2 while ethane produces 2 moles of Co2. Under same conditions, these can be translated to volume. Hence the total volume absorbed is 10 cm3 + 20 cm3 = 30 cm3.
The answer is Silver (Ag)
