Question

The diagram shows a chemistry demonstration. Step 1: Iron and sulfur are mixed together in a test tube; Step 2: The test tube is heated; Step 3: The test is allowed to cool. Which statement best describes this demonstration? Step one contains a compound, which is chemically combined in step two, forming a mixture in step three; step one contains a compound, which is physically combined in step two, forming a mixture in step three; step one contains a mixture of elements, which are physically combined in step two, forming a new compound in step three; step one contains a mixture of elements, which are chemically combined in step two, forming a new compound in step three)

Answer 1

The correct statement that best describes the demonstration is: "Step one contains a mixture of elements, which are chemically combined in step two, forming a new compound in step three."

Explanation:

1. Step 1 - Iron and sulfur are mixed together, which results in a mixture of elements (iron and sulfur are both elements).
2. Step 2 - When the mixture is heated, a chemical reaction occurs, resulting in the formation of iron sulfide, which is a new compound.
3. Step 3 - After cooling, the new compound (iron sulfide) remains in the test tube.

Thus, this demonstration effectively illustrates the transformation from a mixture of elements to a chemically combined compound.