90 grams due to laws of conservation of mass. Output mass = input mass. Mass can never be created or destroyed.
Turns into vapor. not all of the molecules are liquid have the same energy
There are 12 Hydrogens (H) and 12 Oxygens (O) and 6 molecules of Hydrogen Peroxide (H2O2) reacted
Molar mass Argon = 39.948 g/mol
1 mol ------ 39.948 g
mol ----- 20.0 g
mol = 20.0 * 1 / 39.948
= 0.5006 moles
1 mol --------------------- 22.4 L ( at STP )
0.5006 moles ------------- L
L = 0.5006 * 22.4
= 11.21 L
hope this helps!