Answer:-
molecules.
Solution:- The grams of tetrabromomethane are given and it asks to calculate the number of molecules.
It is a two step unit conversion problem. In the first step, grams are converted to moles on dividing the grams by molar mass.
In second step, the moles are converted to molecules on multiplying by Avogadro number.
Molar mass of
= 12+4(79.9) = 331.6 g per mol
let's make the set up using dimensional analysis:

=
molecules
So, there will be
molecules in 250 grams of
.
We can calculate how long the decay by using the half-life equation. It is expressed as:
A = Ao e^-kt
<span>where A is the amount left at t years, Ao is the initial concentration, and k is a constant.
</span><span>From the half-life data, we can calculate for k.
</span>
1/2(Ao) = Ao e^-k(30)
<span>k = 0.023
</span>
0.04Ao = Ao e^0.023(t)
<span>t = 140 sec</span>
<span>Abbreviated systematic numbering for Linolenic Acid is,
18:3, n-3
Explanation:
In above abbreviation
18 specifies number of carbon atoms in Linolenic Acid,
3 specifies the number of double bonds and
n-3 specifies the position of first double bond from methyl end. The structure of Linolenic Acid is as follow,</span>
Answer:
See Explanation
Explanation:
Let us find the number of moles of each element
For iron = 2.24g/56 = 0.04 moles
For oxygen = 0.96 g/16 = 0.06 moles
Then we divide by the lowest ratio;
0.04/0.04 and 0.06/0.04
1 and 2
We Thus obtain 1 : 1.5
Multiplying through by 2 we have; 2 : 3
The formula of the oxide formed is Fe2O3
The balanced equation is;
4Fe + 3O2 ------> 2Fe2O3