# CHEMISTRY

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1. Consider the following reaction:
Pb(NO3)2+KI--> Pbl2 +KNO3
in theis experiment, 12.0g of Kl is reacted with 20.5g of Pb(NO3)2.
a) write a balanced equation for this reaction.
b)identify the limiting reaction.
c)calculate the mass of KNO3 produced from this reaction.

• CHEMISTRY - ,

Pb(NO3)2 + 2KI ==> PbI2 + 2KNO3

b. mols KI = 12.0/molar mass KI.
mols Pb(NO3)2 = 20.5/molar mass Pb(NO)3)2.
Convert mols KI to mols KNO3 using the coefficients in the balanced equation.
Do the same for Pb(NO3)2 to mols KNO3.
It is likely these two valus will not agree which means one of them is not right; the correct value in limiting reagent problems is ALWAYS the smaller value and the reagent producing that number is the limiting reagent.

c. Using the smaller value for mols KNO3, g = mols x molar mass. = grams KNO3.

• CHEMISTRY - ,

dear sir, can you give example more specific...i'm struggle hard to understand it but still not get it..i'm strongly weak for this subject..plz