Statements: (1) Oxygen is a gas. (2) This cylinder contains gas. Conclusion: This cylinder contains oxygen. How should this conclusion be classified?

Introduction / Context:
This question tests your ability to evaluate a conclusion based on two simple statements about gases. Oxygen is identified as a gas, and the cylinder is said to contain gas. The conclusion then claims that the cylinder contains oxygen. The central issue is whether the fact that oxygen is one example of a gas is sufficient to conclude that any container holding gas must be holding oxygen in particular.

Given Data / Assumptions:

• Statement 1: Oxygen is a gas.
• Statement 2: This cylinder contains gas.
• Conclusion: This cylinder contains oxygen.
• No information is given about what kind of gas is inside the cylinder.
• We know that many different gases exist besides oxygen.

Concept / Approach:
The reasoning used in the conclusion is faulty. From the fact that oxygen belongs to the category of gases, and the fact that the cylinder contains some gas, it does not logically follow that the gas present must be oxygen. The cylinder could contain nitrogen, carbon dioxide, helium or any other gas. The premises only tell us that oxygen is an example of a gas and that the cylinder holds at least one gas, but they do not identify which gas. Therefore, the conclusion must be classified as false in terms of logical inference from the given statements.

Step-by-Step Solution:
Step 1: Understand Statement 1 as saying that oxygen is one member of the broader class of gases. Step 2: Understand Statement 2 as saying that the cylinder contains at least one type of gas, but it does not name that gas. Step 3: Notice that many substances are gases, such as nitrogen, oxygen, hydrogen, helium and carbon dioxide. Step 4: The conclusion that the cylinder contains oxygen assumes that because oxygen is a gas and the cylinder has gas, the gas must be oxygen. Step 5: This is a classic logical error similar to saying "a dog is an animal, this cage contains an animal, therefore the animal is a dog." The conclusion does not follow. Step 6: Because there is no information specifying the gas inside the cylinder, claiming specifically that it contains oxygen is logically incorrect. Step 7: Hence the conclusion is false when judged as a deduction from the given statements.

Verification / Alternative check:
To further clarify, imagine two situations. In one, the cylinder holds nitrogen; in the other, it holds oxygen. Both situations satisfy Statement 2, because both contain gas. Statement 1 remains true in both situations, because oxygen is a gas. However, the conclusion "this cylinder contains oxygen" is true in one situation and false in the other. This shows that the conclusion is not guaranteed by the premises and is therefore not valid as a logical deduction. For classification purposes in a reasoning test, it is best described as false in this context.

Why Other Options Are Wrong:
It cannot be called True, because there is no basis in the statements to assert that the specific gas is oxygen. Probably true is also not appropriate, because there is no probabilistic evidence; many gases are commonly stored in cylinders. Irrelevant is unsuitable because the conclusion concerns the same topic, namely the gas in the cylinder, and is directly related to the statements, just incorrectly inferred.

Common Pitfalls:
Students sometimes confuse the idea that oxygen is a gas with the idea that any gas must be oxygen. This is an example of a reasoning error where membership in a category is mistaken for identity. Whenever you see a pattern "X is a Y, Z is a Y, therefore Z is X," you should be cautious. In most cases, this pattern is invalid unless there is additional information that uniquely links X and Z. In reasoning questions, always look for such missing links before accepting a conclusion.

Final Answer:
The conclusion that the cylinder contains oxygen is false, given the information provided.