Answer:
d. 114.8 u
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
<u>For first isotope:
</u>
% = 95.72 %
Mass = 114.9041 u
<u>
For second isotope:
</u>
Since the element has only 2 isotopes, so the percentage of second is 100 - first percentage.
% = 100 % - 95.72 % = 4.28 %
Mass = 112.9043 u
Average Mass = ?
Thus,
<u>Average atomic mass = 114.8 u</u>
<span>When a compound is decomposed into constituent elements, the amount of elements produced will remain in the same proportion every time it is decomposed. When the second sample of calcium fluoride is decomposed, the proportion of calcium and fluorine should remain same as first time.
Hence, calcium produced = 294 * 0.154/0.146 = 309 mg or 0.309 g</span>
Answer:
15
Explanation:
because since the outer shell has 5 electron then add 5 and 10 to get 15
N(H₂O):n(NO)=6:4(3:2), n(NO)=2·3,5mol÷3=2,33mol
So it is a).