*Note: there seems to be a "typo" in the given problem. The "1000" must probably be "100" only since summing up the total number of atoms given for the different isotopes would not equal 1000 but 100 instead. Using 1000 as the basis for the mass fractions would give an answer which is 10 times less than should be.
To determine the average atomic mass of halfnium, the mass fractions of the isotopes multiplied by their respected atomic masses must all be added.
1. Determining the mass fractions (m1, m2...m5) with 100 atoms total as the basis:
m1 = 5/100 = 0.05
m2 = 19/100 = 0.19
m3 = 27/100 = 0.27
m4 = 14/100 = 0.14
m5 = 35/100 = 0.35
2. Multiplying the mass fractions with the atomic masses of the respective isotopes.
Average atomic mass of Halfnium
= (m1*176) + (m2*177) + (m3*178) + (m4*179) + (m5*180)
= (0.05*176) + (0.19*177) + (0.27*178) + (0.14*179) + (0.35*180)
= 178.55 amu
Thus, the average atomic mass of Halfnium based on the given data for its isotopes is 178.55 amu.
Ok so this is what we know :
2KClO3 -> 2KCl + 3O2 (Always check if equation is balanced - in this case it is)
4.26moles
So we know that we have 4.26 moles of oxygen (O2). Now lets look at the ratio between KClO3 and O2.
We see that the ratio is 2:3 meaning that we need 2KClO3 in order to produce 3O2.
Therefore divide 4.26 by 3 and then multiply by 2.
4.26/3 = 1.42
1.42 * 2 = 2.84
Now we know that the molarity of KClO3 is 2.84 moles.
Multiply by R.M.M to find how many grams of KClO3 we have.
R.M.M of KClO3
K- 39
Cl- 35.5
3O- 3 * 16 -> 48
---------------------------
<span>122.5
</span>2.84 * 122.5 = 347.9 grams therefore the answer is (a)
348 grams needed of KClO3 to produce 4.26 moles of O2.
Hope this helps :).
What is the theoretical yield of aluminum oxide if 2.40 mol of aluminum metal is exposed to 2.10 mol of oxygen?<span><span>Ask for details </span><span>Follow </span>Report</span><span> by <span>Sapperd2248 </span><span>1 minute ago
1879</span></span>
Answer: light, chlorophyll,
Explanation:
Light energy drives the synthesis of carbohydrates from corbondioxide and water with the generation of oxygen. Meanwhile chlorophyll helps in the capturing of this light energy.
I believe it is C “Human activities such as mining and deforestation can change the Earth’s surface”