Since Alai is hitting each with a hammer, the physical property which he must be comparing on the two materials must be hardness. Solubility can be tested when you put them in a solvent. Odor can be tested with smell. Conductivity can be tested with electricity. Hardness can be tested with its resistance to the force that hits it.
Two or more different elements
Here’s the math for your answer, which is 3.3 L HCl
They don't change what the substance really is unlike chemical change. They chemical formula of the substance stays the same even though the substance can go under shape change.
