posted by Katie on .
Mercury and bormine react with each other to produce mercury(II)bromide:
Hg + Br2 -> HgBr2
a) What mass of HgBr2 can be produced from the reactiion 10g HG and 9g Br2? [the part that really confuses me] What mass of which reagent is left unreacted?
b) What is the mass of HgBr2 can be produced form the reaction 5ml HG (density=13.6) and 5ml bromine (density=3.1)?
This is the question. I cannot get the right answer, and I'm unsure on how to do it. Can you pleaseeeeeeeeeeeeeee help me?
You get around the "which reagent is in excess" by the following.
Convert 10 g Hg t moles. moles = grams/molar mass.
Convert 9 g Br2 to moles the same way.
Now, using the coefficients in the balanced equation, convert moles Hg to moles of the product.
Do the same for the moles Br2 to moles of the product.
It is likely that the two answers will not agree which means one of them is wrong. The correct answer, in limiting reagent problems is ALWAYS the smaller value and the reagent producing that value is the limiting reagent. This should take care of your problem.
Post your work if you get stuck.