How many electron groups exist at the central c atom in a molecule of methane ch4?

What will most likely happen when two bromine atoms bond together?

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added

How do you calculate the mass of a product when the amounts of more than one reactant are given?