Suppose you have a mixture that contains CaCl2, plus other compounds that do not react with AgNO3. If 0.2918
g of the mixture yields 0.4462 g of AgCl, what is the percentage of CaCl2 in the mixture (thats what was missing from the prior q). Also what did you mean when you said go to the front of the class?
Going to the front of the class means going to the head of the class which means you have done a very very good job and you're at the top of the class. It's a very high compliment.
2AgNO3 + CaCl2 ==> 2AgCl + Ca(NO3)2
mols AgCl obtained = grams AgCl/molar mass AgCl = 0.4462/143.34 (but confirm that--I'm just reciting from memory) = approx 0.003
mols CaCl2 you started with = approx 0.003 x(1 mol CaCl2/2 mols AgNO3) = ?
%CaCl2 = (g CaCl2/mass sample)*100 = ?
Better confirm all those numbers and calculations.
To find the percentage of CaCl2 in the mixture, we need to use the given information that 0.2918 g of the mixture yields 0.4462 g of AgCl.
To solve this question, we can set up a proportion:
(0.4462 g AgCl / Total mass of mixture) = (Mass of CaCl2 / Total mass of mixture)
We know the mass of AgCl and the mass of the total mixture, so we can rearrange the equation to solve for the mass of CaCl2:
Mass of CaCl2 = (0.4462 g AgCl / Total mass of mixture) * Total mass of mixture
Now, let's calculate the mass of CaCl2:
Mass of CaCl2 = (0.4462 g / (0.4462 g + 0.2918 g)) * 0.2918 g
= (0.4462 g / 0.738 g) * 0.2918 g
= 0.6039 g
Now, to find the percentage of CaCl2 in the mixture, we can use the formula:
Percentage of CaCl2 = (Mass of CaCl2 / Total mass of mixture) * 100
Percentage of CaCl2 = (0.6039 g / (0.4462 g + 0.2918 g)) * 100
= (0.6039 g / 0.738 g) * 100
= 81.9%
Therefore, the percentage of CaCl2 in the mixture is 81.9%.
As for your second question, "going to the front of the class" is a phrase often used in a classroom setting. It means that someone is called to stand at the front of the class, usually to address the whole class or take a leading role in some way. In this context, it was just a figure of speech to emphasize that I am trying to provide helpful and clear explanations for your question.