Question
It is found that 1.431 g of element X contains 7.509 × 1021 atoms. The atomic mass of X is?
Answers
Devron
1.431 g of element X=7.509 × 10^21 atoms
1 mole=6.02 x 10^23 atoms, so
7.509 × 10^21 atoms*(1 mole/6.02 x 10^23 atoms)=moles of element X
(moles of element X/1.431 g of element X)=(1 mole/ atomic mass), solve for atomic mass
atomic mass=(1.431 g of element X/moles of element X)
1 mole=6.02 x 10^23 atoms, so
7.509 × 10^21 atoms*(1 mole/6.02 x 10^23 atoms)=moles of element X
(moles of element X/1.431 g of element X)=(1 mole/ atomic mass), solve for atomic mass
atomic mass=(1.431 g of element X/moles of element X)
mike
i got 114.5 is this right?
DrBob222
I don't get that answer but close.
7.509E21/6.022E23 = ?
molar mass = 1.431/? = 114.76 which I would round to 114.8 to four significant figures. Since the data is to four places I used an extra place in 6.022 number but that doesn't account for the slight difference. You may be reading your calculator at the first calculation and rounding too much.
7.509E21/6.022E23 = ?
molar mass = 1.431/? = 114.76 which I would round to 114.8 to four significant figures. Since the data is to four places I used an extra place in 6.022 number but that doesn't account for the slight difference. You may be reading your calculator at the first calculation and rounding too much.