3.2g of a mixture of kn03 and nan03 was heated to constant weight which was found to be 2.64g. What is the % kn03 in mixture
the answer 44.22%
If I get time I will look at this, but really you need a chemistry teacher.
2KNO3 ==> 2KNO2 + O2 and
2NaNO3 ==> 2NaNO2 + O2
Let X = mass KNO3
and Y = mass NaNO3
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eqn 1 is X + Y = 3.2
eqn 2 is
X(molar mass KNO2/KNO3) + Y(molar mass NaNO2/NaNO3) = 2.64
Solve the two equations simultaneously to find X, then
%X = (mass X/3.2)*100 = ?
To find the percentage of KNO3 in the mixture, you need to calculate the mass of KNO3 in the mixture and then express it as a percentage of the total mass.
Let's assume the mass of KNO3 in the mixture is x grams. Since the total mass of the mixture is 3.2g, the mass of the NaNO3 in the mixture can be calculated as (3.2g - x g).
According to the given information, when the mixture is heated to constant weight, the final mass of the mixture is 2.64g. This means that the total mass of KNO3 and NaNO3 after heating is 2.64g.
Since the final mass is the sum of the masses of KNO3 and NaNO3, we can set up the following equation:
x g (mass of KNO3) + (3.2g - x g) (mass of NaNO3) = 2.64g (final mass)
Simplifying the equation, we get:
x + 3.2 - x = 2.64
Simplifying further, we get:
3.2 - 2.64 = x
0.56 = x
Therefore, the mass of KNO3 in the mixture is 0.56g.
To calculate the percentage of KNO3 in the mixture, we divide the mass of KNO3 by the total mass of the mixture, and then multiply by 100:
Percentage of KNO3 = (mass of KNO3 / total mass of mixture) * 100
Percentage of KNO3 = (0.56g / 3.2g) * 100
Percentage of KNO3 ≈ 17.5%
Therefore, the percentage of KNO3 in the mixture is approximately 17.5%.