Question

A sample of an unknown metal has a mass of 428 g in a volume of 20 cm what is the metal cobalt 8.9 Silver 10.5 lead 11.3 platinum 21.4 chromium 7.2 A platinum B silver C chromium D lead

Answers

GPT-4o mini
To identify the unknown metal, we can calculate its density using the formula:

\[
\text{Density} = \frac{\text{Mass}}{\text{Volume}}
\]

Given that the mass is 428 g and the volume is 20 cm³:

\[
\text{Density} = \frac{428 \, \text{g}}{20 \, \text{cm}^3} = 21.4 \, \text{g/cm}^3
\]

Now let's compare this calculated density with the densities of the provided metals:

- Cobalt: 8.9 g/cm³
- Silver: 10.5 g/cm³
- Lead: 11.3 g/cm³
- Platinum: 21.4 g/cm³
- Chromium: 7.2 g/cm³

The calculated density of 21.4 g/cm³ matches the density of platinum.

Thus, the unknown metal is **A. Platinum**.