# Chemistry+need help checking work

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Using aervage atmoic masses for each of the following elements, calculate the mass, in amu (grams)

A. 635 atoms of hydrogen

---> 1 mole of H = 1.01g = 6.022 x 10^23 atom

635 atom of H 1.01g/6.022 x 10^23 atom

I got 1.06 x 10^-21 amu. I got that answer buying the "E" button on my calculator. Instead of putting 6.022 x 10^23 I just put 6.022E23

But if I use the "^" I get 1.07 x 10^25

Which one is right?

• Chemistry+need help checking work -

the one with the E.

• Chemistry+need help checking work -

Ah I also have another question.

I forgot to ask my teacher this, but when I used the "^" on this problem I got the right answer.

Computer the number of atoms of Al of a 10.0g sample

---> moles of Al = 26.981g = 6.022 x 10^23

I ended up with 2.23 x 10^23 as an answer using "^"

I just checked myself by using the "E" and I still got the same answer.

• Chemistry+need help checking work -

1.06 X 10^-21.
The E button is the calculator's way of "x 10^something"; therefore, that answer is the good one. Punching the ^ button, gives you the number raised to some power. The E button raises 10 (not some number punched in) to a power that you add.

• Chemistry+need help checking work -

For example

Wouldn't 8E4 = 8 x 10^4?

• Chemistry+need help checking work -

The 2.23 x 10^23 is correct. I just looked at my calculator and I don't have a ^ so scratch my explanation for that part. I have a yx on mine and I thought that's what you were referring to.

• Chemistry+need help checking work -

No, I think I'll just stick with the "E" for these kind of problems.

• Chemistry+need help checking work -

Right. Stick with E. You KNOW that one is correct.