## anonymous 4 years ago what is the mass in grams of 2.90x10^12 lead (Pb) in atoms ?

1. Mertsj

What is the atomic weight of Pb?

2. anonymous

207.2

3. Mertsj

$2.90\times 10^{12}atoms Pb \times\frac{1 mole Pb}{6.023\times 10^{23}atoms Pb}\times\frac{207.2 g Pb}{1 mole Pb}$

4. Mertsj

I think that works out to 9.98 x10^-10

5. anonymous

how do you figure out the correct scientific notation ?

6. Mertsj

I just plug it into my calculator

7. Mertsj

But if you can't do that then do this:

8. Mertsj

$\frac{2.90(207.2)}{6.023}=99.8$

9. Mertsj

Now we must do the powers of 10

10. Mertsj

$\frac{10^{12}}{10^{23}}=10^{-11}$

11. Mertsj

So now we have: $99.8\times 10^{-11}$

12. anonymous

thank you !!

13. Mertsj

And we need to put that into scientific notation. Can you do that?

14. anonymous

yes sir/ma'am

15. Mertsj

Good for you.