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Answer:</h2>
Valance electrons can be determined by <u>Group</u> on the periodic table
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Explanation:</h2>
- Valence electrons are the electrons present in the outermost shell of an atom. We can determine the total number of valence electrons present in an atom by checking at its Group in which it is placed in the periodic table. For example, atoms in Groups 1 the number of valence electron is one and for group 2 the number of valence electrons is 2.
- The groups have number of valance electrons as follow:
Group 1 - 1 valence electron.
Group 2 - 2 valance electrons.
Group 13 - 3 valence electrons.
Group 14 - 4 valance electrons.
Group 15 - 5 valence electrons.
Group 16 - 6 valence electrons.
Group 17 - 7 valence electrons.
Group 18 - 8 valence electrons.
Result: No of valence electron can be determined by the group no. of the element.
Answer:
There was 450.068g of water in the pot.
Explanation:
Latent heat of vaporisation = 2260 kJ/kg = 2260 J/g = L
Specific Heat of Steam = 2.010 kJ/kg C = 2.010 J/g = s
Let m = x g be the weight of water in the pot.
Energy required to vaporise water = mL = 2260x
Energy required to raise the temperature of water from 100 C to 135 C = msΔT = 70.35x
Total energy required = 

Hence, there was 450.068g of water in the pot.
Balanced equation: 2Fe + 3H2O → Fe2O3 +3H2
Convert g to mols:
285/55.845 = 5.1034 mols
Mole ratio of Iron and Iron (III) Oxide: 2:1
5.1034/2 = 2.5517 mols