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nadezda [96]
2 years ago
15

BRAINLIEST IF ANSWERED CORRECTLY WITH EXPLANATION! HELP PLEASE:)

Chemistry
1 answer:
elena-14-01-66 [18.8K]2 years ago
4 0

First question

Pb(NO_3)_2 + KI \rightarrow PbI_2 + KNO_3

Balaneced:

Pb(NO_3)_2 + 2KI \rightarrow PbI_2 + 2KNO_3

Find how many moles potassium iodide it is in 345.0 grams

n_{KI} = \frac{345.0 \ g}{166.0 \ g/mol} = 2.078 \ mole

Find how many moles potassium nitrate there is for 2.078 moles KI

n_{KNO_3} = \frac{2}{2} \cdot n_{KI} = 2.078 \ mole

Find how many grams potassium nitrate there is in 2.078 moles KNO_3

m_{KNO_3} = 2.078 \ mol \cdot 101.1 \ g/mol = 210.1 \ g

Second question

yield \ \% = \frac{experimental}{theoretical} \cdot 100 = \frac{195.3 \ grams}{210.1 \ grams} \cdot 100 = 93.0 \ \%

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