Explanation:
science can answer any and all questions
This statement is false. When water is decomposed into hydrogen and oxygen; these gases are in a position of combining again to reform water. Water is a molecule consisting of one atom of oxygen bound to two hydrogen atoms. The atoms are joined by covalent bonds; however they have addition hydrogen bonds between the partial negative oxygen and the partial positive hydrogen atom.
All chemical reactions are chemical changes. The Law of Conservation of Matter states that matter cannot be created or destroyed. In a physical change, substances can change form, but the total mass remains the same. In a chemical change, the total mass of the reactants always equals the total mass of the products.
Answer is: 4) The same subscripts are on each side of the equation.
For example, balanced chemical reaction:
2Mg + O₂ → 2MgO.
1) The same number of atoms is on each side of the equation: two magnesium atoms and two oxgen atoms.
2) The formulas for all substances are correct: in magnesium oxide (MgO), magnesium has oxidation number +2 and oxygen -2, so formula is good, because compound must be neutral.
3) The same mass is represented on each side of the equation: because there is same number of atoms, the mass is the same.
4) The same subscripts are on each side of the equation: oxygen does not have same subscripts.
