Question

From the given information, select the suitable law of chemical combination:

• A. Law of Multiple Proportions
• B. Gay Lussac's Law of Gaseous Volumes
• C. Law of Definite Proportions
• D. Law of Conservation of Mass

Hint:

To differentiate between the Law of Definite and Multiple Proportions:

• \textbf{Definite Proportions}: Compares different samples of the \textit{same} compound.
• \textbf{Multiple Proportions}: Compares \textit{different} compounds made from the \textit{same} elements (e.g., CO and CO\(_2\)).

Answer 1

The Correct Option is C

Step 1: Analyzing the given data.
The table shows the percentage composition by mass of copper (Cu), carbon (C), and oxygen (O) in two different samples of cupric carbonate. One sample is obtained from a natural source, and the other is synthesized in a laboratory. The data shows that both samples have the exact same percentage composition: 51.35% Cu, 9.74% C, and 38.91% O.
Step 2: Defining the Laws of Chemical Combination.

• Law of Multiple Proportions: If two elements form more than one compound, the masses of one element that combine with a fixed mass of the other element are in a ratio of small whole numbers.
  
• Gay Lussac's Law: When gases react, they do so in volumes which bear a simple whole number ratio to one another and to the volume of the products, if gaseous.
  
• Law of Definite Proportions (or Constant Composition): A given chemical compound always contains its component elements in a fixed ratio by mass, regardless of its source or method of preparation.
  
• Law of Conservation of Mass: Mass can neither be created nor destroyed in a chemical reaction.
  

Step 3: Applying the correct law.
The observation that cupric carbonate has the same composition whether it is natural or synthetic directly illustrates the Law of Definite Proportions. The chemical identity of a compound is defined by its fixed elemental composition by mass.
Step 4: Final Answer:
The given information illustrates the Law of Definite Proportions.