A solution contains 10 g of KNO3 per 100 g of water at 30˚C. Is the solution unsaturated, saturated or supersaturated?

Explanation:    As you can see, potassium nitrate has s solubility of about  

67 g / 100g H

2

O

at  

40

∘

C

. This means that at  

40

∘

C

, a saturated potassium nitrate solution will contain  

67 g

of dissolved salt for every  

10 0g

of water.

You know that at this temperature, your solution contains  

35 g

of potassium nitrate in  

100 g

of water. This solution will be unsaturated because it contains less potassium nitrate than the maximum amount that can be dissolved.

In order to make a saturated solution, you must get the total mass of potassium nitrate to  

67 g

, which means that you must add

mass of KNO

3

a

to be added

=

67 g

−

35 g

=

∣

∣

∣

∣

¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

a

a

32 g

a

a

∣

∣

−−−−−−−−

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.