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help in chemistry please!?

im taking chem right now and my friends and i need help on this problem:

The element europium exists in nature as two isotopes: 151Eu has a mass of 150.9196 amu, and 153Eu has a mass of 152.9209 amu. The average atomic mass of europium is 151.96 amu. Calculate the relative percent abundance of the two europium isotopes.

Hint: what do you know about the sum of the two percent


whats is the relative percent abundances anyway and how can we calculate it?


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It’s been a long time, been a long time indeed!

But relative abundance is how often each isotype occurs, compared to each other. In thiscase there are only two so it’s just working out x the abundance out of 1 of the smaller isotope and y – the abundance of the larger one.

You have (x*150.9196)+(y*152.9209)=151.96 but y = 1-x

so (x*150.9196 +152.9209- x*152.9209 =151.96




That is the smaller isotope occurs 48.014% of the time (the large occurs 51.986 of the time

That 151.96 up there just won’t show up properly


Use this site to help you with this. I learned this but forget. Sorry


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