1)After burning, the mass of the ash is lighter than the mass of the wood.
2)After burning, the mass of the product, magnesium oxide is heavier than the mass of the magnesium ribbon. ( Burns the ribbon)
3) In a chemical reaction, the total mass of the reactants equals the total mass of the products.
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So let see, in 3) this is because the atoms reactants and products must be the same. Then why in 2)
the mass of the product is heavier than the mass of the reactants ( ribbon)?
Shouldn’t it be the same?
And according to 3) then the mass of the wood in 1) should also be the same how come it is different? I know the mass of ash is of course lighter than wood, but if you combine all the ash together wouldn’t it be the same? Please explain 1) 2) 3) to me why it is different I don’t get it. Thank you.
Edit: I understand it now my stupid ignorant 14-year-old brain didn’t think of the external factors which caused the mass of the ash to be lighter.
In: Physics
You seem to be ignoring the masses of the gases in the reactants and products.
When burning wood, carbon in the wood reacts with oxygen to form carbon dioxide gas. Thus some solid mass is consumed when forming gaseous products.
The opposite holds for the magnesium example: gaseous oxygen is consumed by reacting with solid magnesium, producing a solid product. Thus the mass of the oxide should be greater than the mass of the metal reactant.
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