When (8.30x10^-1) g of silver nitrate is dissolved in water and then mixed with excess potassium iodide solution (6.0000x10^-1) g of precipitate form. What is the percent yield of the reaction? (Answer to 3 s.d. and in proper scientific notation)

2 Answers
Apr 13, 2017

Unknown on the given data...........

Explanation:

We interrogate the following reaction:

AgNO_3(aq) + KI(aq) rarr AgI(s)darr + KNO_3(aq)

Silver iodide, a canary yellow solid, may be treated as insoluble in aqueous solution, the losses probably occur on handling.........

For a "1:1 rxn", "% yield" = "Moles of product"/"Moles of reactant"xx100%.

We have "moles of reactant" (or at least we can calculate it), we have no data on the mass, i.e. the moles of product..........

Apr 13, 2017

See the explanation for the process and solutions.

Explanation:

Balanced Equation

"AgNO"_3("aq") + "KI(aq)"rarr"KNO"_3("aq") + "AgI(s)"

The overall process for answering this question is:

color(red)("given mass AgNO"_3"rarrcolor(red)"mol AgNO"_3"rarrcolor(blue)"mol AgI"rarrcolor(blue)"mass AgI"

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color(red)("given mass AgNO"_3:
8.30xx10^(-1)"g AgNO"_3"

In order to determine mol "AgNO"_3", its molar mass must be determined.

"Molar Mass" M"(AgNO"_3)":

Multiply the subscript of each element by its atomic weight on the periodic table in g/mol, then add them.

M"(AgNO"_3)":(1xx107.8682"g/mol Ag")+(1xx14.007"g/mol N")+(3xx15.999"g/mol O")=color(red)("169.8722 g AgNO"_3"

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

color(red)("Moles AgNO"_3":

Multiply the given mass of "AgNO"_3" by the reciprocal of its molar mass.

8.30xx10^-1color(red)cancel(color(black)("g AgNO"_3))xx(1"mol AgNO"_3)/(169.8722color(red)cancel(color(black)("g AgNO"_3)))=color(red)(4.8860xx10^(-3)"mol AgNO"_3"

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color(blue)("Moles AgI":

Multiply mol "AgNO"_3" by the mol ratio (1"mol AgI")/(1"mol AgNO"_3) from the balanced equation.

4.8860xx10^(-3)color(blue)cancel(color(black)("mol AgNO"_3))xx(1"mol AgI")/(1color(blue)cancel(color(black)("mol AgNO"_3)))=color(blue)(4.8860xx10^(-3)"mol AgI"

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In order to determine the mass of "AgI" produced from the given mass of "AgNO"_3", the molar mass must be determined.

M"(AgI)":

(1xx107.8682"g/mol Ag")+(1xx126.90447"g/mol I")=color(blue)("234.773 g/mol AgI"

color(blue)("Mass AgI":

Multiply mol "AgI" by its molar mass.

4.8860xx10^(-3)"mol AgI"xx(234.773"g"/"mol" "AgI")=color(blue)(1.15xx10^0"g AgI"

The theoretical yield of "AgI" from 8.30xx10^(-1)"g AgNO"_3" is 1.15xx10^0"g AgI".

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

"% yield"=("actual")/("theoretical")xx100

"% yield"=(6.0000xx10^(-1)"g AgI")/(1.15xx10^0"g AgI")xx100=5.22xx10^1 %