question_answer 1)

  Greenhouse effect leads to global warming. Which substances are responsible for greenhouse effect?

Answer:

  The various gases which bring greenhouse effect responsible for global warming are -the following with relative contributions : Relative contribution (i) Carbon dioxide                            50% (ii) Water vapour             2% (iii) Nitrous oxide             4% (iv) Ozone                                           8% (v) Chlorofluorocarbons                17% (vi) Methane                                     19%