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​Would the mass of remaining Ash from a burnt paper be the same as that of the paper burnt ?

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​During a chemical reaction matter is neither created or destroyed even though it might appear that way . Matter is changed into another form affecting the mass of the original reactants

Law of Conservation of Mass

by Garfield Baker

​This is called the Law of Conservation of Mass. The Law of Conservation of Mass states that during a chemical Reaction mass is neither created or destroyed

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In a chemical reaction the starting mass of the reactants must be the same as that of the products .

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​The reason was that the water vapor and CO₂ escaped in the air . It is not destroyed but just changed the state that it was in .

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​This happens in a OPENED SYSTEM

​In an OPEN SYSTEM matter can enter or leave increasing or decreasing the mass of the final product . For example when baking soda and vinegar is mixed and the gas escaped that is an OPEN system

​In a CLOSE SYSTEM no matter is able to enter in the reaction as a result the mass is not affected . For example if Vinegar and Baking Soda is mixed together and Covered no matter ( mass) will be added or lost ,because nothing will be able to enter or leave

Does the equation below that represent a chemical reaction shows the Law of Conservation of mass to be true ?

Balancing Equations

• ​Because we know that the reactants should be the same as that of the products but is not the case in an OPEN system , Chemical Equations must be balanced

• ​Balancing Equation satisfies the LAW of CONSERVATION OF MASS

• ​To do this Coefficient are added before the elements or compounds

• Coefficient are used to multiply the subscript (number of atoms ) of each elements until both sides are equal

​Chose different elements and add keep adding coefficient until both sides are balanced (same). If there is a subscript when a Coefficient is added they will multiply together . Ex. there were 2 O atoms and a Coefficient of 11 was added making it 22

​Make a Table to show how many atoms of each elements are present on either sides

​This Equation is not balanced . There are 7 Carbon (C) atoms on left while there is 1 on the right. There are 16 Hydrogen(H) on the left while 2 are on the right . There are 2 Oxygen on the on the left while 3 on the right

​Is this Equation Balanced ?

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​ 2 Al₂O₃-------- 4Al + 3O₂

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​ Reactant Product

​ Al = 4 Al = 4

​ O = 6 O= 6

​Reactants Product

Al - 2 Al - 1

O - 3 O - 2