Question

this table compares four metals.

metal	melting point (°c)	density (g/cm³)	flame test color	electrical conductivity
lead	327.5	11.34	blue/white	poor
tin	231.93	5.77	blue/white	fair
iron	1538	7.87	gold	good

a sample known to be one of the four listed metals was heated to a temperature of 350°c but remained a solid. the sample was found to have a density greater than 6 g/cm³ and to be a good conductor of electricity. burning the sample produced a blue flame. what is the identity of this sample?

○ zinc

○ lead

○ tin

○ iron

Explanation:

1. Analyze the melting point: The sample was heated to 350°C and remained solid, so its melting point must be above 350°C.

• Zinc: 419.53°C (above 350°C)
• Lead: 327.5°C (below 350°C, eliminated)
• Tin: 231.93°C (below 350°C, eliminated)
• Iron: 1538°C (above 350°C)

1. Analyze electrical conductivity: The sample is a good conductor.

• Zinc: Good (retained)
• Iron: Good (retained)
• Lead: Poor (already eliminated)
• Tin: Fair (already eliminated)

1. Analyze density: The sample has a density greater than 6 g/cm³.

• Zinc: 7.14 g/cm³ (greater than 6)
• Iron: 7.87 g/cm³ (greater than 6)

1. Analyze flame test color: The sample produces a blue flame.

• Zinc: Blue (matches)
• Iron: Gold (does not match, eliminated)

After checking all criteria, only Zinc meets all the conditions (melting point > 350°C, good conductivity, density > 6 g/cm³, blue flame).

Answer:

Zinc