please help me. i don't understand this at all.
a sample of nickle has 2.5 times the mass of a sample of calcium with 203 x 10^23 molecules. what is the mass of the nickle?
atomic mass of nickle: 58.6934
calcium: 40.078
avagadro's number: 6.022 x 10^23
2007-11-01 06:41:35 · 4 answers · asked by the common cold 4 in Science & Mathematics ➔ Chemistry
Moles Ca = 203 x 10^23 / 6.022 x 10^23 = 33.71
Atomic weight Ca = 40.078 g/mol
Mass Ca = 40.078 g/mol x 33.71 = 1351 g
Mass Ni = 2.5 x 1351 = 3377.5 g
2007-11-01 06:50:04 · answer #1 · answered by Dr.A 7 · 1⤊ 0⤋
1st convert the number of atoms to the mass by using # of Ca Atoms
203*10 (23) x 40.078g/6.022*10(23)
This will give you the mass of CA
1351.018598 g
From here you take the mass of the CA and since the nickle has 2.5 times the mass of CA multiply the Ans by 2.5 and your done.
3377.546496g
2007-11-01 06:55:09 · answer #2 · answered by CRSP 5 · 2⤊ 0⤋
203x10^23atomsCa x 1molCa/6.02x10^23atomsCa x 40gCa/1molCa x 100gNi/40gCa = 3.37g Ni
The factor 100gNi/40gCa in the middle expresses the fact that there is 2.5 times as much nickel as calcium.
2007-11-01 06:49:10 · answer #3 · answered by steve_geo1 7 · 1⤊ 1⤋
let go!!!!!!!!!!
2007-11-01 06:45:04 · answer #4 · answered by paradiseemperatorbluepinguin 5 · 0⤊ 1⤋