If you know the mass and volume of a coin, which method would best allow you to determine if the coin is not pure silver?

• A. Observe the coin's color and compare it to the appearance of pure silver.
• B. Test the coin's electrical conductivity and compare it to pure silver.
• C. Calculate the density of the coin and compare it to the known density of pure silver.
• D. Measure the melting point of the coin and compare it to that of pure silver.

Answer: (C)

Verified step by step guidance

1. Understand that the problem is asking for a method to determine if a coin is pure silver based on its mass and volume.
2. Recall that density is defined as mass divided by volume, given by the formula \(\text{Density} = \frac{\text{Mass}}{\text{Volume}}\).
3. Calculate the density of the coin by dividing the measured mass by the measured volume using the formula above.
4. Compare the calculated density of the coin to the known density of pure silver (approximately 10.49 g/cm³).
5. If the coin's density significantly differs from the known density of pure silver, it suggests the coin is not pure silver.