# When heated, KClO3 decomposes into KCl and O2. If this reaction produced 20.3 g of KCl, how much O2 was produced (in grams)?

##”13.1 g O”_2##

Start by writing the balanced chemical equation that describes the of potassium chlorate, ##”KClO”_3##, to form potassium chloride, ##”KCl”##, and oxygen gas, ##”O”_2##

##2″KClO”_text(3(s]) -> color(red)(2)”KCl”_text((s]) + color(blue)(3)”O”_text(2(g]) uarr##

Notice that for every two moles of potassium chlorate that undergo decomposition, you get ##color(red)(2)## moles of potassium chloride and ##color(blue)(3)## moles of oxygen gas.

You can convert this ##color(red)(2):color(blue)(3)## that exists between the two products of the reaction to a gram ratio by using the molar masses of the two .

##”For KCl”: ” ” M_M = “74.55 g mol”^(-1)##

##”For O”_2: ” ” M_M = “32.0 g mol”^(-1)##

This tells you that every mole of potassium chloride has a mass of ##”74.55 g”##, which implies that ##color(red)(2)## moles will have a mass of

##2 color(red)(cancel(color(black)(“moles KCl”))) * “74.55 g”/(1color(red)(cancel(color(black)(“mole KCl”)))) = “149.1 g”##

For oxygen gas, every mole has a mass of ##”32.0 g”##, which means that ##color(blue)(3)## moles will have a mass of

##3 color(red)(cancel(color(black)(“moles O”_2))) * “32.0 g”/(1color(red)(cancel(color(black)(“mole O”_2)))) = “96.0 g”##

The ##color(red)(2):color(blue)(3)## mole ratio will be equivalent to a ##149.1 : 96.0## gram ratio, i.e. you get ##”96.0 g”## of oxygen gas for every ##”149.1 g”## of potassium chloride produced by the reaction.

This means that ##”20.3 g”## of potassium chloride would correspond to

##20.3color(red)(cancel(color(black)(“g KCl”))) * “96.0 g O”_2/(149.1color(red)(cancel(color(black)(“g KCl”)))) = “13.07 g O”_2##

Rounded to three , the number of sig figs you have for the mass of potassium chloride, the answer will be

##m_(O_2) = color(green)(|bar(ul(color(white)(a/a)”13.1 g”color(white)(a/a)|)))##

## Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
\$26
The price is based on these factors:
Number of pages
Urgency
Basic features
• Free title page and bibliography
• Unlimited revisions
• Plagiarism-free guarantee
• Money-back guarantee
On-demand options
• Writer’s samples
• Part-by-part delivery
• Overnight delivery
• Copies of used sources
Paper format
• 275 words per page
• 12 pt Arial/Times New Roman
• Double line spacing
• Any citation style (APA, MLA, Chicago/Turabian, Harvard)

# Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

### Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

### Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

### Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.