Balance the following reaction: _mg+_o2=_mgo

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?

Why do cells appear different in distilled water than they do in 10% salt water?

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.