Let's analyze the student's investigation of lead by categorizing each property as either physical or chemical.
1. Color - Physical property
2. Density - Physical property
3. Volume of sample - Physical property
4. Melting point - Physical property
5. Reaction with air - Chemical property
6. Electrical conductivity - Physical property
Now, count the number of physical and chemical properties:
- Physical properties: 5 (color, density, volume of sample, melting point, electrical conductivity)
- Chemical properties: 1 (reaction with air)
Comparing the counts:
- Physical properties: 5
- Chemical properties: 1
Thus, the statement that is true with respect to the investigation is:
"The student investigated more physical properties than chemical properties of lead."
So the answer is:
"The student investigated more physical properties than chemical properties of lead."