Question

What mass of potassium chlorate would contain 40 grams of oxygene

Answer 1

Answer:

24.5 g

Step-by-step explanation:

The first thing to do here is to write a balanced chemical equation that describes this decomposition reaction

2KClO3(s)→2KCl(s)+3O2(g)↑⏐

Notice that it takes 2 moles of potassium chlorate to produce 3 moles of oxygen gas.

This means that if you know how many moles of oxygen gas were produced by the reaction, you can backtrack and use this 2:3 mole ratio to figure out how many moles of potassium chlorate underwent decomposition.

Now, STP conditions, which were probably given to you as a pressure of 1 atm and a temperature of 0∘C, are characterized by the fact that one mole of any ideal gas occupies 22.4 dm3 -- this is known as the molar volume of a gas at STP.

Use this value to calculate how many moles of oxygen gas were produced by the reaction

6.72dm3⋅ mole O222.4dm3=0.30 moles O2

This means that the decomposition reaction consumed

0.30moles O2⋅2amoles KClO33moles O2=0.20 moles KClO3

Now all you have to do is use the molar mass of potassium chlorate to calculate how many grams would contain this many moles

0.20moles KClO3⋅122.5 g1mole KClO3=∣∣ ∣∣¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯aa24.5 gaa∣∣−−−−−−−−−−

Answer 2

Answer : The mass of potassium chlorate is, 102.125 grams

Step-by-step explanation:

Potassium chlorate is a compound that contains potassium, chlorine and oxygen atom. The molecular formula potassium chlorate is,
`KClO_3`

From the molecular formula potassium chlorate we conclude that, there are 1 atom of potassium, 1 atom of chlorine and 3 atoms of oxygen.

The mass of 3 oxygen atom = 3 × 16 = 48 g

The molar mass of potassium chlorate = 122.55 g/mole

As, 48 gram of oxygen present in 122.55 grams of potassium chlorate

So, 40 gram of oxygen present in
`(40)/(48)* 122.55=102.125` grams of potassium chlorate

Therefore, the mass of potassium chlorate is, 102.125 grams