1.The Volume of oxygen required for the complete combustion of 500ML of ethyne at STP..A)2.00ML B)1.25 C)1.71 D)1.00
2.A Chemical Engineer finds that 250ml CuSO4 reacts with excess NaOH to create 2.37g of precipitate.Calculate the Concentration of copper(II) Sulphate solution.
3.Propane is a useful fuel for camping.If 50.0L of propane undergoes complete combustion at STP.Calculate the volume of water vapour produced at STP.
4.How many grams of calcium chloride can be prepared if a student uses 500g if calcium carbonate and 2.00L of a 4.00 Mol/L sodium chloride solution in the reaction.
5. 2KMnoO4 + 5 H2C2O4<----need to use this
Concentration of 0.24L KMnO4 solution required to oxidize 2.7g of Oxalic Acid???
6.What volume of 0.100mol/L aqueous sodium hydroxide(NaOH) is neutralized by 500ml of 0.200mol/L hydrochloric acid(HCI)
7.When 10.0g of potassium chlorate,KCIO3,decomposes,what volume of oxygen is obtained(at 18C and 750 mm HG pressure)
8. 2(NH4)3PO4-->3N2+O2+12H2+2PO3
a)name products
b)Name the reactant
c)type of reaction
6 answers
The balanced equation of the combustion:
2C2H2 + 5O2 -> 4CO2 + 2H20
tell us that 2 volumes of ethylene reacts with 5 volumes of oxygen.
Answer : B. 1.25 litre
2.A Chemical Engineer finds that 250ml CuSO4 reacts with excess NaOH to create 2.37g of precipitate.Calculate the Concentration of copper(II) Sulphate solution.
CuSO4 + 2NaOH -> Na2SO4 + Cu(OH)2
Molecular weight of CuSO4 = 159.546
THerefore there are 2.37g/159.546=0.1485 mol in 500 ml. Thus the concentration of CuSO4 is 0.0297 mol/litre.
NOTE: water vapour condenses below 100 deg. The volume calculated is the converted equivalent of water vapour at STP.
C2H8 + 7O2 -> 3CO2 + 4H2O
Thus each volume of C2H8 produces 4 volumes of water vapour. So 50 litres of propane produces 200 l. of water vapour.
1 answer