Answer:
has 4 electrons in its valence shell.
Explanation:
Silicon has 14 protons, so its neutral atom has also 14 electrons, thus, the electron distribution following the Linus Pauling's diagram is:
1s² 2s²2p⁶ 3s²3p²
Thus, it has 4 electrons in its valence shell (3), likely carbon. So, silicon would have some of the properties of carbon, such as form 4 bonds, and the structure would be similar.
Answer:
will be 90054 J
Explanation:
Number of moles = (mass)/(molar mass)
Molar mass of 
= 134.45 g/mol
So, 1.00 g of = 
of = 0.00744 mol of
0.00744 mol of produces 670 J of heat
So, 1 mol of produces 
of heat or 90054 J of heat
Answer:
the first one I believe is right but I could be wrong.
Difference between Gas and Vapour:
Gas:
A thermodynamic state in which a substance exists only in one phase i.e. Gas phase. In above given examples N₂, He and CO₂ exists as gases at room temperature. These gases cannot form a solid or liquid phase along with gas phase as these states requires very low temperatures.
Vapours:
It is a thermodyanamic state in which a substance exists in more than one phase. In given options Sulfur can exist in vapor state. This is because sulfur exists in a cyclic or chain form due to catenation (self linkage property). Therefore, a lower members of S allotrops can form a vapours.
