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[sammy w]

HEY

im really ill so cant go and see my teacher this week for help for the 2009 exam next wed so would be grateful if i could get loads of help off here!!

2003 MULTIPLE CHOICE

Q5 a mix of sodium chloride and sodium sulphate contains 0.6 moles of chloride ions and 0.2 mol of sulphate ions. how many sodium ions are there?

the answer is 1......??????????????????

Q14 the no. of moles in 1 mol of copper(11) phosphate is.....?? answers is 5........
( solutions say Cu3(PO4)2....i dont get why the 2 on the copper has switched with the 3- on the PO4???

Q 35 when a certain aquesous solution is diluted its conductivity decreases but ph remains constant. the solution could be.....

ethanoic acid, sodium chloride, sodium hydroxide, nitric acid??....is it just knowlegde that the answer is sodium chloride?

Q36 the ion electron equations for a redox reaction are

2I- goes to I2 + 2e-
MnO4- + 8H+ + 5E- goes to Mn(2+) + 4H2O

how many moles of iodide ions are oxidised by 1 mole of permanganate ions...answer 5.........i understand to do redox eqn but i am stuck from there


Please help, would really appreciate it as worrying bout not being well enough for exam as i have tonsilitis!!!

thanks