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1. what mass of iodine is produces when 7.1g of chlorine reacts with excess potassium iodine?
2. (Original post by slowangrytree)
what mass of iodine is produces when 7.1g of chlorine reacts with excess potassium iodine?
Have you got a balanced equation? This will gie you the molr ratios of Iodine to chlorine.
Then just work out the moles of chlorine used in 7.1g and plug into the ratio.
3. (Original post by an_atheist)
Have you got a balanced equation? This will gie you the molr ratios of Iodine to chlorine.
Then just work out the moles of chlorine used in 7.1g and plug into the ratio.
the equation is:
Cl2 + 2 KI = 2 KCl + I2
How does the excess of potassium iodine affect the process? or does it actually change anything?
4. (Original post by slowangrytree)
what mass of iodine is produces when 7.1g of chlorine reacts with excess potassium iodine?
so you got

Cl2 + 2KI = 2KCl + I2

so we know that 7.1 g of Cl2 reacts, therefore the mr of Cl2 is 70 (35.5 x2)

Then we can work out the moles from these 2 data by doing mass / mr which gives us 71/700 (store it in calculator, or write it down somewhere.)

Considering that the ratio of Cl2 and I2 is just 1:1, we now can deduce that I2 is also 71/700 moles.

So far the information which we would know about I2 would then be

The moles = 71/700
the Mr = 127 x 2

Therefore we can then work out the Mass by ultiplying those numbers together.
5. Excess is used typically in a titration right? So it can be neutralised with another substance
6. (Original post by brownguytorule)
so you got

Cl2 + 2KI = 2KCl + I2

so we know that 7.1 g of Cl2 reacts, therefore the mr of Cl2 is 70 (35.5 x2)

Then we can work out the moles from these 2 data by doing mass / mr which gives us 71/700 (store it in calculator, or write it down somewhere.)

Considering that the ratio of Cl2 and I2 is just 1:1, we now can deduce that I2 is also 71/700 moles.

So far the information which we would know about I2 would then be

The moles = 71/700
the Mr = 127 x 2

Therefore we can then work out the Mass by ultiplying those numbers together.
took the words right out my mouth
7. (Original post by Indyyyy)
took the words right out my mouth
of course
8. (Original post by brownguytorule)
so you got
.
thanks a bunch

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