Why do you think that if you drop two balls, exactly two balls rise on the other side at a similar speed? Why doesn’t one ball fly off quickly instead? Why don’t three balls fly off slowly? This is a difficult question, but try your best to think about what you know and what might make sense.

50.23 i believe is correct but don't quote me on that.

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.