Question

Sodium chlorate decomposes into sodium chloride and oxygen gas as seen in the equation below.

­­2NaClO3­ --> 2NaCl +3O2

How many moles of O2 were produced by 4 moles of NaClO3­? Round your answer to the nearest whole number.

Answer 1

Step-by-step explanation:

From the given equation, for every 2 moles of NaClO3, 3 moles of O2 are produced.

So, for 4 moles of NaClO3:

4 moles NaClO3 / 2 moles NaClO3 = 2

Therefore, 2 * 3 moles O2 = 6 moles O2.

So, 4 moles of NaClO3 will produce 6 moles of O2.

Answer 2

16 moles

Step-by-step explanation:

Since we have the ratios of the substances' molar masses, we can just calculate using those. We know that our end product has 3 grams of oxygen; our equation shows that the end product has 3O2 after decomposition, so we can compare how much oxygen we have to how much 3O2 would weigh if we had whole moles of substance.

3O2 would be six moles and weigh 96 grams. Since we only actually have 3 grams, we know that we are working with 3 / 96 = 1/32 of a mole per substance. Now, we look at the equation again, and multiply the ratio of each substance by 1/32, and then by the molar weight. All that's left is finding the importance of the Sodium and the Chlorine, both of which are prevalent in a ratio of 2, so we take 2/32=1/16 of each substance and multiply by their molar weights; 23/16 grams of Sodium, and 35.5/16 grams of Chlorine. Adding those together, we have 58.5/16 grams, which we can round to 64/16, or 4. Adding those 4 grams to the 3 grams of oxygen that the problem gives us, we have seven grams of Sodium Chlorate necessary to give us 3 grams of oxygen post-decomposition.