Ariver with a flow of 50 m3/s discharges into a lake with a volume of 15,000,000 m3. the river has a background pollutant concentration of 5.6 mg/l. at time zero the concentration in the lake is 5.6 mg/l before an industry begins discharging waste with a flow of 0.7 m3/s also into the lake with a pollutant concentration of 300 mg/l. the decay coefficient for the pollutant in the lake is 0.2 per day. what is concentration leaving the lake one day after the pollutant is added?

Explanation:

The given data is as follows.

       Volume of lake = =

        Concentration of lake = 5.6 mg/l

Total amount of pollutant present in lake =

                                                                    = mg

                                                                    = kg

Flow rate of river is 50

Volume of water in 1 day =

                                          = liter

Concentration of river is calculated as 5.6 mg/l. Total amount of pollutants present in the lake are or

Flow rate of sewage =

Volume of sewage water in 1 day = liter

Concentration of sewage = 300 mg/L

Total amount of pollutants = or

Therefore, total concentration of lake after 1 day =

                                        = 6.8078 mg/l

                  = 0.2 per day

        = 6.8078

Hence, =

              =  

                             = 1.234 mg/l

Hence, the remaining concentration = (6.8078 - 1.234) mg/l

                                                             = 5.6 mg/l

Thus, we can conclude that concentration leaving the lake one day after the pollutant is added is 5.6 mg/l.

answer; talc and gypsum;

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.