Rational number word problem with fractions | Pre-Algebra | Khan Academy

TL;DR

Water expands by about 9% when frozen, leading to an increase in volume.

Transcript

Most liquids, when cooled, will simply shrink. Water, on the other hand, actually expands when it is frozen. Its volume will increase by about 9%. Suppose you have 1/3 of a gallon of water that gets frozen. What is the volume of the ice that you now have? So you're starting with 1/3 of a gallon of water. They tell us that when it gets frozen, when ... Read More

Key Insights

• 💦 Water is one of the few exceptions where its volume increases upon freezing.
• 🥶 The expansion of water when freezing is due to the formation of hexagonal ice crystals.
• 💦 Freezing water can exert tremendous force, damaging containers and structures.
• ❄️ The expansion of water when frozen has implications for weather patterns and ecosystems, as well as geological processes such as frost wedging and ice formation in lakes and rivers.
• 👻 The expansion of water also contributes to the buoyancy of icebergs, allowing them to float.
• 💦 Ice cubes in water often float due to the expansion of the water when frozen.
• 😋 The expansion of water when frozen is utilized in various applications, such as the creation of ice sculptures and the preservation of food.

Questions & Answers

Q: Why does water expand when frozen?

Water has a unique structure that causes it to form hydrogen bonds, which rearrange and space out the molecules when freezing, leading to expansion.

Q: How does the expansion of water affect objects it freezes around?

The expansion of water can be destructive, as it exerts pressure on containers, pipes, and structures, potentially causing them to crack or burst.

Q: Does all water expand by the same amount when frozen?

The expansion of water when freezing is consistent for pure water, but impurities can alter the expansion rate, potentially resulting in different volumes of ice.

Q: Why is it important to express the answer as a fraction?

Expressing the answer as a fraction allows for a precise representation of the volume of ice, taking into account the initial volume of water.

Summary & Key Takeaways

• Most liquids shrink when cooled, but water expands when frozen.

• The volume of 1/3 gallon of water will increase by about 9% when frozen.

• To find the volume of ice after expansion, multiply the original volume by 9% and add it to the original volume.