calculating into grams.?

Question

5.00 x 10^21 formula units of nickel II sulfate


7.66 x 10^19 molecules of hydrogen peroxide

Answer 1

it is all in moles. but its weird because moles use avogadro's number which is (6.02 x 10^23) x the atomic mass of the element or the compound.

NiSO4 and H2O2

2 hydrogen is 2g + 2 oxygen is 32g, so one mole of hydrogen peroxide is 34g. maybe you can build off that.

nickel is 58.5g + sulfur 32g + 4 oxygen 64g, so one mole of nickel II sulfate is 154.5g

i hope this helps :-)

Answer 2

Atomic weights: Ni=59 S=32 O=16 NiSO4=155 H=1 H2O2=34

Let formula units be called fm.

5.00x10^21fmNiSO4 x 1molNiSO4/6.o2x10^23fmNiSO4 x 155gNiSO4/1molNiSO4 = 1.29g NiSO4

7.66x10^19moleculesH2O2 x 1molH2O2/6.02x10^23moleculesH2O2 x 34gH2O2/1molH2O2 = 4.33 x 10^-3g H202

Answer 3

NiSO4 = 58.7 + 32.1 + 4(16.0) = 154

5.00 Exp 21 f.u X 154 g / 6.02 Exp 23 f.u. = 1.28 grams

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H2O2 = 2(1.00) + 2(16) = 34

(34.0 g / 6.02 Exp 23 molecules)(7.66 Exp 19 molecules) = 0.00433 grams