An explosion that occurs at the end of a massive star's life is a ?
a is a large cloud of gas and dust in space.
a low- or medium-mass star becomes a at the end of its life.
a appears to emit regular bursts of radio waves.
a forms from the leftover material from a supernova; it may contain as much as three times the mass of the sun.

In vapor-liquid equilibrium in a binary mixture, both components are generally present in both phases. how many degrees of freedom are there for such a system? the reaction between nitrogen and hydrogen to form ammonia occurs in the gas phase. how many degrees of freedom are there for this system? steam and coal react at high temperatures to form hydrogen, carbon monoxide, carbon dioxide, and methane. the following reactions have been suggested as being involved in the chemical transformation:

Salt in oceans comes from and of rocks

If 2 molecules of one reactant combine with 3 molecules of another to produce 5 molecules of a product, then what is the representation of the reaction?