3Si + 2N2 --> Si3N4 (as given)
n(Si) = m/MM = 38.25/28.085 = 1.3619 mol
n(N2) = 14.33/2*14.007 = 0.5115 mol
Therefore, N2 is limiting and Si is in excess
The molar ratio of 2N2:Si3N4 is 2:1
So, 0.0575 mol of silicon nitride is formed (dividing 0.5115 by 2)
m of silicon nitride= n*mm = 0.0575*140.283 = 8.06627... g
= 8.066g (4 significant figures)
(hopefully it is right, but double check in case i did something wrong) :)
If the sun was not there the earth would travel in a straight line
Answer:
a nonspontaneous redox reaction
<span>This
really depends on how closely related the species are. Species from vastly
unrelated taxonomic groups are likely to have organs that differ substantially.
Think for example of the compound eye of a spider and the eye of a human, or
the bones of a fish compared to the cartilage of a shark. These are examples of species that are not closely related at all. Then think of a chimpanzee and a human. The organs of both species are very similar in form and function as they are closely related. </span>
All of them are properties of compounds except III.
for I, compounds are chemically combined together, so to separate them, we must use chemical methods like electrolysis or applying heat. These requires large amount of energy.
For II, they're always fixed. For example, in water (H2O), the ratio of hydrogen and oxygen is always 1:8 in mass. If there's some extra added, the substance becomes mixture instead of compounds.
For IV, after you chemically combined elements or compounds together, their properties are completely different. For example, iron can be attracted to magnets, but iron II sulphide does not.
