Elemental phosphorus occurs as tetratomic molecules, P4. What mass of chlorine gas is needed for complete reaction with 375 g phosphorus to form phosphorus pentachloride?
2007-09-23 08:36:09 · 3 answers · asked by neena m 1 in Science & Mathematics ➔ Chemistry
let's write the reaction equation
P4+10 Cl2 --> 4 PCl5
Ar P = 30.974 gr/mole thus Mr P4 = 4 x Ar P = 123.896 gr/mole
Ar Cl = 35.453 gr/mole thus Mr Cl2 = 2 x Ar Cl = 70.906 gr/mole
375 g P4 equals (375/123.896) mole P4 = 3.03 mole
according to reaction equation 3.03 mole P4 require exactly 30.3 mole of Cl2 = 30.3 x Mr Cl2 = 30.3 x 70.906 = 2.15 kg Cl2
Conclusion: you need 2.15 kg Cl2 to react completely with 375 P4
2007-09-23 08:48:27 · answer #1 · answered by IonicLiquids 2 · 0⤊ 0⤋
P4 + 10 Cl2 = 4 PCl5
375 g P4 x 1 mol P4 / 124 g P4 = 3.02 mol P4
3.02 mol P4 x 10 mol Cl2 / mol P4 = 30.2 mol Cl2
30.2 mol Cl2 x 71 g/mol = 2140 g Cl2
2007-09-23 08:41:46 · answer #2 · answered by Fly On The Wall 7 · 0⤊ 0⤋
P4 + 10Cl2 = 4PCl5
Molar Ratios are 1:10 :: 4
Moles(P) = 375/31(Mr(P)) = 12.097 (this is equivalent to '1')
Moles(Cl) = 12.097 x 10 = 120.97 (this is equivalent to '10').
Mass(Cl) = 120.97 x 71(Mr (Cl2)) = 340.482 g
2007-09-23 08:47:00 · answer #3 · answered by lenpol7 7 · 0⤊ 0⤋