Question

Liquefied petroleum gas (LPG) mainly contains

• A. Methane, Ethane
• B. Ethane, Propane
• C. Butane, Isobutane
• D. Ethene, Ethyne

Hint:

Remember the main components of common fuel gases:
- Natural Gas: Primarily Methane (C1).
- LPG: Primarily Propane (C3) and Butane (C4).
- Gasoline: A mix of hydrocarbons from C4 to C12.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
We have to express the hardness produced by MgCl₂ as CaCO₃ equivalent in parts per million.

Step 2: Key Formula or Approach:
Use the equivalent mass conversion followed by the ppm calculation based on the sample weight.

Step 3: Detailed Explanation:
Converting 19 mg of MgCl₂ into CaCO₃ equivalent gives \(20\) mg. Since this is dissolved in 2 kg of water, the hardness becomes \(20/2=10\) mg/kg, which is the same as 10 ppm.

Step 4: Final Answer:
The hardness of the sample is 10 ppm.