Question

A sample known to be one of the four listed in the table was heated to a temperature of 35C but remained a solid. The sample was found to have a density greater than 6 g/cm3and to be a good conductor of electricity. Burning the sample produced a blue flame. Based on this information, what is the identity of this sample?

A) Copper (Cu)
B) Silver (Ag)
C) Magnesium (Mg)
D) Lead (Pb)

Answer 1

The sample with a density greater than 6 g/cm3 that conducts electricity and produces a blue flame when burned is Copper (Cu).

Step-by-step explanation:

Based on the information provided, the identity of the sample can be deduced by considering its physical properties at 35°C, its density, electrical conductivity, and the color of flame it produces when burned. Since the sample remains a solid at 35°C, we can exclude any element with a melting point below this temperature. Considering the density to be greater than 6 g/cm³, this excludes elements with lower densities. Good electrical conductivity suggests that the substance is a metal. The blue flame produced upon burning indicates the presence of copper, as it is characteristic for this metal. Therefore, the sample is identified as A) Copper (Cu).