Question

1. table salt can be separated into sodium and chlorine. sodium is explosive. chlorine is a gas that can kill people. what can be concluded from the statements above? a. a harmful compound can become harmless when its elements are separated. b. a harmless compound can become harmful when its elements are separated. c. breaking a compound into its separate elements has no noticeable effects. d. breaking a compound into its separate elements can create carbon dioxide.

Explanation:

• Table salt (\(NaCl\)) is a compound. Sodium (\(Na\)) is explosive and chlorine (\(Cl_2\)) is a harmful gas. But when they combine to form \(NaCl\), it is harmless. This shows that a compound's properties are different from its constituent elements. When a compound is broken into its elements (like \(NaCl\) into \(Na\) and \(Cl_2\)), the properties of the elements (harmful, explosive) are shown. So, a harmful compound (\(NaCl\) is not harmful, but take a general case like some toxic compounds) can become harmless when its elements are separated (opposite of the example here, but conceptually, the properties change when compound is broken into elements).
• Option A: A harmful compound can become harmless when its elements are separated. For example, if we consider a compound like phosgene (\(COCl_2\), harmful) which can be decomposed. When decomposed, the properties of elements (e.g., carbon, oxygen, chlorine - chlorine is harmful) are different from the compound. But in the table - salt example, the compound (\(NaCl\)) is harmless and elements (sodium is explosive, chlorine is harmful gas). But the key concept is that compound properties are different from element properties. When a compound (which may be harmful) is broken into elements, the element properties (which may be harmless in some combinations) can emerge.
• Option B: A harmless compound (\(NaCl\)) can become harmful when its elements are separated (sodium is explosive, chlorine is harmful gas).
• Option C: Breaking a compound into its separate elements has a noticeable effect (as the properties of elements are different from the compound).
• Option D: Breaking a compound into its separate elements (e.g., \(NaCl\) into \(Na\) and \(Cl_2\)) does not create carbon dioxide.

Answer:

B. A harmless compound can become harmful when its elements are separated.