What is the mass of 7.21 x 1021 molecules of silver acetate? Plez show how to do this, thanx
2007-01-15 03:40:15 · 3 answers · asked by xo winter-angel xo 3 in Science & Mathematics ➔ Chemistry
its suppose to be 10^21
2007-01-15 03:44:52 · update #1
One mole = 6.022 * 10^23 molecules = one gram molecular mass (or weight) of a compound.
You need to divide the number of molecules (7.21 * 10^21) by 6.022 * 10^23 to get the number of moles. This is the same as (7.21/6.022) * (10^21)/(10^23) = (7.21/6.022) * (1/100).
The molar mass (molecular weight) of Silver acetate is 166.91 g/mol. You can get this by adding all the atomic masses for all of the elements in AgC2H3O2. Now, multiply the number of moles found above by 166.91 g/mol to get the number of grams of the Silver acetate..
2007-01-15 03:51:23 · answer #1 · answered by Richard 7 · 16⤊ 3⤋
I'm not sure I like your "it's supposed to be" answer.
First calculate the moleculare weight of silver acetate from its formula and the atomic weights of the atoms in the molecule. So the formula for silver acetate is AgC2H3O2.
When you calculate the molar mass (molecular weight), that will give you the mass in grams of one mole of the compound. Since one mole is 6.02 X 10^23 molecules, you can calculate the mass of any part of a mole. So, if you divide 7.21 X 10^21 by 6.02X10^23, that will give you the number of moles. Then, multiply that by the molecular weight, and you have the mass (in grams) of 7.21 X 10^21 molecules.
2007-01-15 11:50:02 · answer #2 · answered by hcbiochem 7 · 3⤊ 0⤋
do it yourself or you'll never learn how
2007-01-15 11:47:29 · answer #3 · answered by Anonymous · 1⤊ 3⤋