Identify each of the following as a physical or chemical change:
a. Aspirin tablets are broken in half.

Verified step by step guidance

1. Step 1: Understand the difference between physical and chemical changes. A physical change involves a change in the physical state or appearance of a substance without altering its chemical composition. Examples include changes in shape, size, or state (e.g., melting, freezing). A chemical change, on the other hand, involves a transformation that changes the chemical composition of the substance, often producing new substances (e.g., rusting, burning).
2. Step 2: Analyze the given scenario. Breaking an aspirin tablet in half involves changing its size and shape, but the chemical composition of the aspirin remains unchanged.
3. Step 3: Determine whether the change is physical or chemical. Since the chemical structure of the aspirin is not altered and no new substances are formed, this is a physical change.
4. Step 4: Confirm your reasoning. Breaking the tablet does not involve any chemical reaction, such as a change in bonds or the formation of new compounds, which further supports that this is a physical change.
5. Step 5: Conclude that breaking an aspirin tablet in half is a physical change because it only affects the physical appearance (size and shape) of the tablet without altering its chemical composition.

Key Concepts

Physical Change

A physical change involves a transformation that does not alter the chemical composition of a substance. Examples include changes in state, shape, or size, such as breaking, dissolving, or melting. In the case of aspirin tablets being broken in half, the tablets remain chemically the same; only their physical form is altered.

Chemical Change

A chemical change results in the formation of one or more new substances with different chemical properties. This process often involves a chemical reaction, where bonds between atoms are broken and formed. Unlike physical changes, chemical changes are usually irreversible under normal conditions, such as burning or rusting.

Distinguishing Changes

To distinguish between physical and chemical changes, one can assess whether the substance's identity remains intact. If the change can be reversed and the original substance can be recovered, it is likely a physical change. Conversely, if new substances are produced and the original cannot be easily restored, it indicates a chemical change.