Question

Identify the characteristic of gold shown in the table that allows gold to be deposited behind the riffl es, while other material fl ows out of the sluice box as tailings. [1]

Answer 1

The characteristic of gold that allows it to be deposited behind the riffles in a sluice box is its high density. The high density of gold causes it to settle behind the riffles while lighter materials are carried away as tailings.

Step-by-step explanation:

Characteristic of Gold Allowing Deposition Behind Riffles

The characteristic of gold that allows it to be deposited behind the riffles while other material flows out of the sluice box as tailings is its high density. Gold is a dense metal, with a density of 19.3 g/cm³, which is much higher than the density of other common materials found in rivers, such as sand and gravel. When water flows through the sluice box, the high density of gold causes it to settle behind the riffles, while the lighter materials are carried away.

To better understand this, imagine you have a river with flowing water and a sluice box, which is a long, narrow channel designed to capture gold. The sluice box is lined with riffles, which are ridges or barriers that help create turbulence in the water. As the water flows through the sluice box, the riffles disrupt the flow, causing the heavier gold particles to settle behind them. This allows the gold to be trapped and collected, while the lighter materials flow out of the sluice box as tailings.

Answer 2

The characteristic in question is the density - which is relatively high for Gold (and higher than water).

A high density means that the particles of gold will flow towards the bottom of the container.

It's also mentioned in the text: "the more dense gold to drop out"