Copper has two naturally occurring isotopes. Cu-63 has a mass of 62.939 amu and relative abundance of 69.17%. Use the atomic weight of copper to determine the mass of the other copper isotope.

fraction*mass + fraction*mass = atomic mass Cu.

You know fraction and mass of one isotope. Th fraction of the second isotope is 1.00-fraction of first, and the periodic table gives you the atomic mass Cu. Solve for mass of second.

Is this for webassign? Cause I had that exact same problem lol does all of the USA use webassign?

Just wondering

well, I live in Indiana, West Lafayette and I am not sure all of the USA use webassign, and yes this is webassign

To determine the mass of the other copper isotope, we need to first find the atomic weight of copper using the given information.

The atomic weight is the weighted average of the masses of all the naturally occurring isotopes of an element, taking into account the relative abundances of each isotope.

Here's how you can calculate the atomic weight of copper:

1. Start by multiplying the mass of each isotope by its relative abundance:
Cu-63: 62.939 amu * 69.17% = 43.542 amu

2. Next, subtract this product from the atomic weight of copper:
Atomic weight of copper - mass of Cu-63 = mass of the other copper isotope

Let's calculate it:

Atomic weight of copper - 43.542 amu = mass of the other copper isotope

The atomic weight of copper is usually given as 63.546 amu (you can find this information in the Periodic Table).

63.546 amu - 43.542 amu = 20.004 amu

Therefore, the mass of the other copper isotope is approximately 20.004 amu.