Laws of Matter

If two or more different compounds are composed of the same two elements, then the ratio of masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers.

• Law of Conversation of Mass

• Law of Definite Proportion

• Law of Multiple Proportion

• Law of Matter

States that mass is neither created nor destroyed in a chemical reaction.

• Law of Conversation of Mass

• Law of Definite Proportion

• Law of Multiple Proportion

• Law of Matter

This states that a compound is always composed of the same elements in the same proportion by mass, no matter how large or small the sample is.

• Law of Conversation of Mass

• Law of Definite Proportion

• Law of Multiple Proportion

• Law of Matter

Who said that all samples of a compound have the same composition - the same proportions by mass of the constituent elements.

• John Daton

• Antoine Lavoisier

• John Proust

• Charles Darwin

A pure sample of Benzene (C6H6) contains 68g of Carbon. How many grams of Hydrogen is present in the sample?

Consider two compounds formed by carbon and oxygen: carbon dioxide (CO₂) and carbon trioxide (CO₃). In carbon dioxide, 12 grams of carbon combined with 32 grams of oxygen. In sulfur trioxide, 12 grams of carbon combine with 48 grams of oxygen. Show that these data obey the Law of Multiple Proportions.

CH4 + O2 --> CO2 + H2O

Give the total mass of each compound.

(Example: CaCO3 --> CaO + CO2)

Answer: CaCO3 = 100g CaO = 56g CO2 = 44g