If i leave 750 ml of 0.75 m sodium chloride solution uncovered on a windowsill and 150 ml of the solvent evaporates, what will the new concentration of the sodium chloride solution be? m1v1 = m2v2

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.