2 mg + o2 → 2 mgo how many grams of mgo are produced when 40. 0 grams of mg react completely with o2? molar mass of mg is 24. 31 g/mol, and of o is 16. 00 g/mol.

17 a tourist was planning a trip by car for travelling at some constant speed for 2.5 hours. however, he found that if he increases the speed by 20 km/h he can cover the same distance in 30 minutes less time than it was planned. what was the planned speed of the tourist, in km/h?