Answer:
Physical change
Explanation:
A physical change is one in which no new substance is formed and can be reversed using physical methods.
When we mix the salt and water, we have merely carried out a physical change. No new substance was formed. To recover the salt, we simply heat the solution to dryness.
Hence, this is an example of a physical change.
It is either the 3rd answer or the 4th answer. Both are correct ways to write hydrates, but I was taught the 4th way. Just make sure this answer matches the format of the examples your teacher gave you.
Answer:
2KClO3 ==> 2 KCl + 3O2
393g O2 x 1 mole/32 g = 12.28 moles O2
moles KClO3 needed = 12.28 mol O2 x 2 mol KClO3/3mol O2 = 8.19 mol
grams KClO3 = 8.19 moles x 123g/mol = 1007g
Explanation:
Question:
What is the total combined mass of carbon dioxide and water that is produced?
Answer:
<u><em>109 kg</em></u>
Explanation:
When 23 kg of gasoline burns by consuming 86 kg oxygen, they produce carbon dioxide and water. To find the total combined mass of carbon dioxide and water, we will use mass conversation law.
According to mass conversation law, the mass of the product is equal to the mass of reagent.
Mass of reagent = Mass of product
In this reaction,
Gasoline + O2 → CO2 + H2O
23 kg + 86 kg → ?
23 kg + 86 kg = 109 kg
Combined mass of carbon dioxide and water will be 109 kg.
Answer:
The molarity of a sugar solution is 2 M.
Explanation:
Molarity is a concentration measure that expresses the moles of solute per liter of solution. In this case it is calculated with the simple rule of three:
4 L of solution--------8 moles of sugar
1 L of solution ------x= (1 L of solution x 8 moles of sugar)/4 L of solution
x=2 moles of sugar---> <em>The solution is 2M</em>
