Given the following table:
| color | dull gray |
| ------------------- | ------------------------------ |
| density | $11.3 g / cm ^3$ |
| volume of sample | $3.00 cm^3$ |
| melting point | $327^{\circ} C$ |
| reaction with air | lead oxide forms on the surface |
| electrical conductivity | conducts some electricity |
Which statement is true with respect to the investigation?
A. The student investigated only the physical properties of lead.
B. The student investigated only the chemical properties of lead.
C. The student investigated more physical properties than chemical properties of lead.
D. The student investigated more chemical properties than physical properties of lead.
Answer (1)
Identify physical properties: color, density, volume, melting point, electrical conductivity.
Identify chemical properties: reaction with air.
Count the number of physical properties: 5.
Count the number of chemical properties: 1. The student investigated more physical properties than chemical properties of lead.
Explanation
Analyzing the Problem We need to analyze the given properties of lead to determine which statement about the investigation is true.
Identifying Physical Properties First, let's identify the physical properties. Physical properties are those that can be observed without changing the substance's chemical identity. From the table, the physical properties are:
Color: dull gray
Density: 11.3 g / c m 3
Volume of sample: 3.00 c m 3
Melting point: 32 7 ∘ C
Electrical conductivity: conducts some electricity
Identifying Chemical Properties Next, let's identify the chemical properties. Chemical properties describe how a substance changes during a chemical reaction. From the table, the chemical property is:
Reaction with air: lead oxide forms on the surface
Counting Properties Now, let's count the number of physical and chemical properties.
Number of physical properties: 5
Number of chemical properties: 1
Determining the True Statement Comparing the number of physical and chemical properties, we see that there are more physical properties (5) than chemical properties (1). Therefore, the statement 'The student investigated more physical properties than chemical properties of lead' is true.
Examples
Understanding the properties of materials like lead is crucial in various fields, such as engineering and construction. For instance, knowing the density and melting point of lead helps engineers determine its suitability for use in radiation shielding or soldering. Similarly, understanding its reaction with air helps in designing protective coatings to prevent corrosion. By investigating these properties, students can learn how to select appropriate materials for specific applications and design durable structures.
