51: The only coefficient is in the first one i think and it would be a 3
52: Neon (Ne)
53: Mg has a low nuclear charge so all it's electrons would be lost in the electron shell, making the ion smaller than the atom.
Heat from fire or heat from the sun warming your face
Ice floats because it is about 9% less dense than liquid water. ... The heavier water displaces the lighter ice, so ice floats to the top. One consequence of this is that lakes and rivers freeze from top to bottom, allowing fish to survive even when the surface of a lake has frozen over
