Properties of Water Worksheet KEY - Name: Period: ____ Properties ... - Free Printable
Educational worksheet: Properties of Water Worksheet KEY - Name: Period: ____ Properties .... Download and print for classroom or home learning activities.
PNG
1200×1553
288.7 KB
Free · Personal Use
Quality Assured by Worksheets Library Team
Reviewed for educational accuracy and age-appropriateness
ID: #1754382
⭐
Show Answer Key & Explanations
Step-by-step solution for: Properties of Water Worksheet KEY - Name: Period: ____ Properties ...
▼
Show Answer Key & Explanations
Step-by-step solution for: Properties of Water Worksheet KEY - Name: Period: ____ Properties ...
You've uploaded a completed "Properties of Water Worksheet" with answers filled in red. Below is a detailed explanation for each answer to help you understand the science behind water’s unique properties.
---
✔ Explanation: In a water molecule (H₂O), each hydrogen atom shares electrons with the oxygen atom. This sharing of electrons forms a covalent bond. Oxygen is more electronegative, so it pulls the shared electrons closer — leading to unequal sharing (which makes the molecule polar).
---
✔ Explanation: Because oxygen has a higher electronegativity than hydrogen, it pulls the shared electrons toward itself. This creates a partial negative charge (δ⁻) on the oxygen and partial positive charges (δ⁺) on the hydrogens. This uneven distribution of charge makes water a polar molecule.
---
✔ Explanation: Polar molecules like water can surround and separate ions or other polar molecules. For example, when salt (NaCl) dissolves, water molecules surround Na⁺ and Cl⁻ ions, pulling them apart. This ability to dissolve many substances earns water the title "universal solvent".
---
✔ Explanation: Cohesion is the attraction between like molecules — in this case, water molecules sticking to each other via hydrogen bonds. This is why water forms droplets and has high surface tension.
---
✔ Explanation: The δ⁺ hydrogen of one water molecule is attracted to the δ⁻ oxygen of another. These attractions are called hydrogen bonds — they’re weaker than covalent bonds but strong enough to give water its special properties (like cohesion, high specific heat, etc.).
---
✔ Explanation: Adhesion is the attraction between unlike molecules — for example, water sticking to glass or plant cell walls. This helps water climb up narrow tubes (capillary action) in plants.
---
✔ Explanation: Surface tension is caused by cohesive forces at the surface of water. Molecules at the surface have no neighbors above them, so they pull inward, creating a “skin” that can support small objects (like insects or paper clips).
---
✔ Explanation: Viscosity measures a fluid’s resistance to flow. Cooler water has slower-moving molecules, which increases internal friction → higher viscosity. This helps plankton and small organisms float with less effort.
---
✔ Explanation: Condensation occurs when water vapor (gas) cools and loses energy, turning into liquid water droplets (e.g., dew on grass, fogged-up windows).
---
✔ Explanation: Sublimation skips the liquid phase. Example: dry ice (solid CO₂) sublimes, and so does snow/ice under certain conditions (especially in dry, cold climates).
---
✔ Explanation: Deposition is the reverse of sublimation. Water vapor turns directly into ice without becoming liquid first. Example: frost forming on cold surfaces.
---
✔ Answer: *Water is less dense in solid form because hydrogen bonding between water molecules pushes molecules further apart into a set crystalline pattern.*
✔ Explanation: In liquid water, molecules are close together. When water freezes, hydrogen bonds lock molecules into a hexagonal lattice that takes up more space → lower density. Since ice is less dense than liquid water, it floats — crucial for aquatic life in winter!
---
✔ Answers:
- Higher density
- Conductivity
- Decreased surface tension
✔ Explanation:
- Higher density: Salt ions increase mass per volume → denser than freshwater.
- Conductivity: Dissolved salts (like NaCl) break into ions (Na⁺, Cl⁻), which carry electric current → ocean water conducts electricity.
- Decreased surface tension: Salt disrupts hydrogen bonding at the surface → reduces surface tension slightly compared to pure water.
---
## 🌊 Summary:
Water’s unique properties stem from its polarity and hydrogen bonding. These allow it to act as a universal solvent, exhibit cohesion/adhesion, have high surface tension and viscosity, and display unusual density behavior (ice floats). Adding salt alters some properties — making ocean water denser, conductive, and slightly less surface-tensioned.
Let me know if you’d like diagrams, real-life examples, or practice questions to reinforce these concepts!
---
1. The hydrogen and oxygen atoms are held together by _covalent_ bonds.
✔ Explanation: In a water molecule (H₂O), each hydrogen atom shares electrons with the oxygen atom. This sharing of electrons forms a covalent bond. Oxygen is more electronegative, so it pulls the shared electrons closer — leading to unequal sharing (which makes the molecule polar).
---
2. The electrons are not shared equally creating a _polar_ molecule.
✔ Explanation: Because oxygen has a higher electronegativity than hydrogen, it pulls the shared electrons toward itself. This creates a partial negative charge (δ⁻) on the oxygen and partial positive charges (δ⁺) on the hydrogens. This uneven distribution of charge makes water a polar molecule.
---
3. The polarity of water allows it to _dissolve_ most substances. Because of this it is referred to as the _universal solvent_.
✔ Explanation: Polar molecules like water can surround and separate ions or other polar molecules. For example, when salt (NaCl) dissolves, water molecules surround Na⁺ and Cl⁻ ions, pulling them apart. This ability to dissolve many substances earns water the title "universal solvent".
---
4. Water molecules stick to other water molecules. This property is called _cohesion_.
✔ Explanation: Cohesion is the attraction between like molecules — in this case, water molecules sticking to each other via hydrogen bonds. This is why water forms droplets and has high surface tension.
---
5. Hydrogen bonds form between adjacent water molecules because the _positively_ charged hydrogen end of one water molecule attracts the _negatively_ charged oxygen end of another water molecule.
✔ Explanation: The δ⁺ hydrogen of one water molecule is attracted to the δ⁻ oxygen of another. These attractions are called hydrogen bonds — they’re weaker than covalent bonds but strong enough to give water its special properties (like cohesion, high specific heat, etc.).
---
6. Water molecules stick to other materials due to its polar nature. This property is called _adhesion_.
✔ Explanation: Adhesion is the attraction between unlike molecules — for example, water sticking to glass or plant cell walls. This helps water climb up narrow tubes (capillary action) in plants.
---
7. _Surface tension_ creates the skin-like surface formed due to the polar nature of water.
✔ Explanation: Surface tension is caused by cohesive forces at the surface of water. Molecules at the surface have no neighbors above them, so they pull inward, creating a “skin” that can support small objects (like insects or paper clips).
---
8. _Viscosity_ is the tendency for fluids to resist flow. _Cooler_ water is more viscous than warmer water, allowing floating organisms to use less energy to keep from sinking.
✔ Explanation: Viscosity measures a fluid’s resistance to flow. Cooler water has slower-moving molecules, which increases internal friction → higher viscosity. This helps plankton and small organisms float with less effort.
---
9. _Condensation_ is when water changes from a gas to a liquid.
✔ Explanation: Condensation occurs when water vapor (gas) cools and loses energy, turning into liquid water droplets (e.g., dew on grass, fogged-up windows).
---
10. _Sublimation_ is when water changes from a solid directly to a gas.
✔ Explanation: Sublimation skips the liquid phase. Example: dry ice (solid CO₂) sublimes, and so does snow/ice under certain conditions (especially in dry, cold climates).
---
11. _Deposition_ is when water changes from a gas directly to a solid.
✔ Explanation: Deposition is the reverse of sublimation. Water vapor turns directly into ice without becoming liquid first. Example: frost forming on cold surfaces.
---
12. Why does ice float?
✔ Answer: *Water is less dense in solid form because hydrogen bonding between water molecules pushes molecules further apart into a set crystalline pattern.*
✔ Explanation: In liquid water, molecules are close together. When water freezes, hydrogen bonds lock molecules into a hexagonal lattice that takes up more space → lower density. Since ice is less dense than liquid water, it floats — crucial for aquatic life in winter!
---
13. List the properties that ocean water has due to the fact that it contains salt.
✔ Answers:
- Higher density
- Conductivity
- Decreased surface tension
✔ Explanation:
- Higher density: Salt ions increase mass per volume → denser than freshwater.
- Conductivity: Dissolved salts (like NaCl) break into ions (Na⁺, Cl⁻), which carry electric current → ocean water conducts electricity.
- Decreased surface tension: Salt disrupts hydrogen bonding at the surface → reduces surface tension slightly compared to pure water.
---
## 🌊 Summary:
Water’s unique properties stem from its polarity and hydrogen bonding. These allow it to act as a universal solvent, exhibit cohesion/adhesion, have high surface tension and viscosity, and display unusual density behavior (ice floats). Adding salt alters some properties — making ocean water denser, conductive, and slightly less surface-tensioned.
Let me know if you’d like diagrams, real-life examples, or practice questions to reinforce these concepts!
Parent Tip: Review the logic above to help your child master the concept of 2 2 properties of water worksheet.
