the element boron has two naturally occurring isotopes with masses of 10.01amu and 11.01amu. What is the percent abundance of the first isotope.

You have to know the average atomic mass of boron....look at the periodic table to get that.

Now, the math...

avgatomicmass*100=10.01*P + 11.01*(100-P)

solve for P.

10.81 amu

To find the percent abundance of the first isotope of boron, we need to know the relative abundance of both isotopes.

Let's assume x represents the percent abundance of the first isotope. The percent abundance of the second isotope can then be calculated as 100% - x.

Next, we can use the average atomic mass of boron, which is given by the weighted average of the masses of the two isotopes:

Average atomic mass = (mass of first isotope * percent abundance of first isotope) + (mass of second isotope * percent abundance of second isotope)

However, in this case, we only need to find the percent abundance of the first isotope. So, we can rewrite the equation as:

10.01 amu * x + 11.01 amu * (100% - x) = average atomic mass of boron

Substituting the given values:

10.01 amu * x + 11.01 amu * (100% - x) = average atomic mass of boron

Now, we can solve this equation to find the value of x, which represents the percent abundance of the first isotope.