[MikeTyson]

any help is appreciatede

A sample of sodium peroxide Na2O2 is reachted with excess water

2 Na2O2 (s) + 2 H20 (l) ---> 4 NaOH (aq) + O2 (g)

all of the sodium peroxide reacted, and the oxygen was collected over water at 21.0 degrees Celcius. barometric pressure was 771mmHg
The gas is collected in a graduated container and the level of water inside the tube was 25.0 cm above the level of water outside the tube. If the volume of gas in the tube is 31 mL how many grams of solid peroxide were in the sample (for water at 21 degrees C vapor pressure is 18.7 mmHg and density is 0.998g/cm^3


the final answer turns out to be 0.193g
how do u solve this?

[MikeTyson]

nm i got it... didnt use balanced equation  :oops:

[Jiro]

Here is something to give your brains some mental gymnastics try to do it in your head lol...

How many grams of sodium peroxide must be used to produce 100L oof oxygen gas saturated with water vapor @ 298K and 1.0 atm?  assume the oxygen gas that is collected is saturated with water vapor.

2Na2O2 + 2H2O -> 4NaOH + O2