35.8g of mixture of kcl and kclo3,were heated to constant to a constant mass.if the residue weighed 24.9g,what was the percentage mass of the kcl int the mixture.kcl is not decomposed onm heating
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Solve it for me please
mass KClO3 + mass KCl before heating = 35.8 grams
mass KCl after heating to constant weight = 24.9 grams.
35.8 g - 24.9 =
2KClO3 ==> 2KCl + 3O2.
oops. pushed the wrong button and it posted too early.
mass KClO3 + mass KCl before heating = 35.8 grams
mass KCl after heating to constant weight = 24.9 grams.
35.8 g - 24.9 = 10.9 g = mass lost due to oxygen escaping.
2KClO3 ==> 2KCl + 3O2.
mols O2 lost = 10.9 g/32 = 0.341
mols KClO3 that decomposed = 0.341 x (2 mols KClO3/3 mols O2) = 0.341 x 2/3 = ?
grams KClO3 = moles KClO3 x molar mass KClO3 = ?
mass mixture - mass KClO3 = mass KCl
% KCl in the original mixture = (grams kcl from above/mass sample)100 = ?
To find the percentage mass of KCl in the mixture, we need to determine the mass of KCl and the mass of the total mixture. Here's how we can do that step by step:
1. Start by subtracting the mass of the residue from the initial mass of the mixture to find the mass of the evaporated substances:
Mass of evaporated substances = Initial mass - Residue mass
= 35.8g - 24.9g
= 10.9g
2. Since KCl is not decomposed on heating, the mass of KCl in the evaporated substances is the same as the mass of KCl in the initial mixture. Therefore, we need to find the mass percent of KCl in the evaporated substances.
3. Calculate the mass percent of KCl in the evaporated substances by dividing the mass of KCl by the mass of the evaporated substances and multiplying by 100:
Mass percent of KCl = (Mass of KCl / Mass of evaporated substances) x 100
However, we don't have the mass of KCl yet. So, we need to find that next.
4. Since the mass of the residue is the mass of KCl and KClO3 in the initial mixture, subtract the mass of KClO3 from the mass of the residue to find the mass of KCl:
Mass of KCl = Mass of residue - Mass of KClO3
= 24.9g - Mass of KClO3
5. We can find the mass of KClO3 by subtracting the mass of KCl from the initial mass of the mixture:
Mass of KClO3 = Initial mass - Mass of KCl
= 35.8g - Mass of KCl
6. Using the information from steps 4 and 5, we can substitute the values into step 3's formula to find the mass percent of KCl in the evaporated substances.
That's how you can calculate the percentage mass of KCl in the given mixture by following a step-by-step procedure.