1. ch4 + 202 co2 + 2h20

if you begin with 40g of ch4 and it reacts with 15g of 202 producing

20g of co2, how many grams of 2h20 are produced?

16.36 grams

Explanation:

From the reaction equation:

CH4   +   2O2 CO2     +     2H2O

1         :        2                                    1         :         2

If 20g of CO2 was produced, then the  number of moles of CO2 is given by :

Molar mass of CO2 = 12 + [2 x 16]

                                =  44 gram/moles

Number of moles =  Mass in gram/ Molar mass

=     20/ 44

=     0.4545 moles

if 0.4545 moles of CO2 were produced, then according to the equation of reaction, then:

Number of moles of H2O produced will be = 2 x  0.4545

                                                                         = 0.909moles

Molar Mass of H2O = [1 x2] + [16]

                                 = 18 grams/ mol

The mass of H2O produced will be = Number of moles  x Molar Mass

                                                           =   0.909 moles x  18 grams/mole

                                                           =  16.362 grams

                                                           ≈   16.36 grams

the answer would be a