Salt: Salt and Ice

The video explains how adding salt to water lowers its melting and freezing points by disrupting the water's lattice structure. This principle is used to melt ice on roads. Salt is more effective than other substances like sugar due to its availability and cost. However, as temperatures drop below -7°C, salt becomes less effective, and below -10°C, it has little impact.

What happens to the freezing point of water when salt is added?

• It fluctuates randomly.

• It remains the same.

• It decreases.

• It increases.

Why is salt commonly used on roads during winter?

• It is more expensive than other substances.

• It is less effective than sugar.

• It increases the freezing point of water.

• It is readily available and effective.

How do sodium and chloride ions affect the ice structure?

• They have no effect on the lattice structure.

• They strengthen the lattice structure.

• They make the ice more rigid.

• They disrupt the lattice structure.

What happens to the effectiveness of salt as temperatures drop below -7°C?

• It becomes more effective.

• It remains equally effective.

• It becomes less effective.

• It has no effect at all.

At what temperature does salt have little or no effect on ice?

• 0°C

• -10°C

• -7°C

• -5°C