How much energy is given off by the following reaction, if 162.5 g of oxygen reacts with 216.7 g of ammonia (NH3)?
4 NH3 + 502 → 4 NO + 6H2O H = -1225.6 kJ

Drive down any three characteristic of modern periodic table

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?

An atom's configuration based on its number of electrons ends at 3p4. another atom has seven more electrons. starting at 3p, what is the remaining configuration? 3p63d34s2 3p43d54s2 3p64s23d3 3p44s23d