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Offline jjkwest1

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solution chemistry and bonding question
« on: December 19, 2009, 03:39:23 AM »
You mix 260 ml of 1.2 M lead(II)nitrate with 300 ml of 1.9 M potassium iodide. The lead(II) iodide is insoluable. Which of the following is false?
a. the final concentration of Pb2+ ions is .0482 M
b. you form 131 g of lead (II) iodide
c. the final concentration of K+ is 1.02 M
d. the final concentration of NO3- is 1.02 M

i set the reaction up as:

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

i first found the limiting reactant to be KI

then i got that the a. was false because when i calculated the concentration for Pb2+ i got .508 M

however the answer key said that it was d. I was wondering how? was the answer key wrong?


2. Consider a hypothetical molecule with the skeleton structure N-O-N. In the most reasonable of possible lewis structure, the molecule has___________, and is likely to be ______________

a. a single bond and a triple bond, stable
b. a single bond and a triple bond, unstable
c. two souble bonds, unstable
d. two double bonds, stable

i got that it should be double bond due to the formal charges but can anyone explain to me why it's unstable, since the answer was c. Thanks

Offline UG

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Re: solution chemistry and bonding question
« Reply #1 on: December 19, 2009, 04:42:36 AM »
then i got that the a. was false because when i calculated the concentration for Pb2+ i got .508 M
Please show your calculation for how you got 0.508 M

Offline Borek

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Re: solution chemistry and bonding question
« Reply #2 on: December 19, 2009, 04:53:28 AM »
then i got that the a. was false because when i calculated the concentration for Pb2+ i got .508 M

Check your math.

Draw Lewis structure for ONO and post it.
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