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Answer 1 · 2014-09-19T23:43:23

It will contain enough chloride ions to make 5.28g of magnesium chloride.

Lead (IV) chloride has the formula #PbCl_4#.

Work out the mass of 1 mole by adding up the #Ar# values:

#M_r# = 207.2 +(35.5 x 4) = 349.2

Now we work out how many moles we have in 9.73g since no. moles = mass in grams/mass of 1 mole:

No. moles = 9.73/349.2 = 0.028 mol

From the formula the number of moles of Cl must be 4 x this so:

moles Cl = 0.028 x 4 = 0.11

Now we can work out the mass of chlorine since its #A_r# is 35.5:

Mass Cl = 0.11 x 35.5 = 3.95 g.

How much magnesium chloride will this make?

The formula is #MgCl_2# so The #M_r# is 24 + (35.5 x2) = 95.

So 2x 35.5 = 71g of Cl are needed to make 95g of #MgCl_2#

So 1g of Cl will make 95/71 = 1.34g #MgCl_2#

So 3.95g Cl will make 1.34 x 3.95 = 5.28g #MgCl_2#

It's the use of simple proportion. 6 bananas cost £3. So 1 banana costs 3/6 = £0.5. (that would be 50p in the UK).