This element is Chlorine.
It has 3 energy levels since it is on the third row of the periodic table and it has seven valence electrons since it is in the 17th column (second to last column).
The atomic mass<span> of an element is a weighted average of its </span>isotopes<span> in which the sum of the abundance of each isotope is equal to 1 or 100%.
</span><span>Let fraction of N-15 be x
then fraction of N-14 = 1-x
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<span>Formula for Calculating Isotope:
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on calculation:
x = <span>0.006403
so, % = 0.006403 x 100 = 0.6403 %<span>
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Answer:
2grams as per the question
Water pollution affects the fish, and then we eat the fish so the fish affects us. im not sure about the first part.Do<span> not dispose of household cleaning down the toilet.
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How much NH4Cl can you dissolve in 200 g of water at 90° to make a saturated solution?
C) 140