Answer:
2 grams.
Explanation:
H2 + O2 ---> H2O2
Using molar masses:
2*1 g hydrogen reacts with 2*16 g oxygen.
so 2g H2 reacts with 32 g O2.
Remember that:
number of moles = mass/molar mass
First, we get the molar mass of the nitrogen gas molecule:
It is known the the nitrogen gas is composed of two nitrogen atoms, each with molar mass 14 gm (from the periodic table)
Therefore, molar mass of nitrogen gas = 14 x 2 = 28 gm
Second we calculate the mass of the precipitate:
we have number of moles = 0.03 moles (given)
and molar mass = 28 gm (calculated)
Using the equation mentioned before,
mass = number of moles x molar mass = 0.03 x 28 = 0.84 gm
Use the density to convert volume into mass.
since the density is in g/ml and the volume was given in Liters, we need to first convert the Liters into mililiters. just multiply by 1000 or move the decimal three times.
0.1200 Liters= 120.0 mL
120.0 mL (0.8787 grams/ 1 mL)= 105 grams