How will you distinguish between each to the given pairs of compounds by a single chemical test ?
Ethane and acetylene

Sure, here are the step-by-step solutions for distinguishing between ethane and acetylene using a single chemical test: 1. Choose a reagent that will react differently with ethane and acetylene. One such reagent is bromine water. 2. Add a small amount of bromine water to a test tube containing ethane. \ce{C2H6 + Br2 ->[\text{light}] C2H5Br + HBr} 3. Observe that there is no reaction or color change in the test tube, indicating that ethane does not react with bromine water. 4. Add a small amount of bromine water to a separate test tube containing acetylene. \ce{C2H2 + Br2 ->[\text{light}] C2HBr + HBr} 5. Observe that the bromine water immediately turns from orange to colorless as it reacts with the acetylene to form 1,2-dibromoethene. 6. Conclude that the test has successfully distinguished between ethane and acetylene, as ethane does not react with bromine water while acetylene does.