Properties of Water Flashcards

Properties of Water

• Polarity
  Water is a polar molecule where oxygen holds electrons more tightly than hydrogen, resulting in a slight negative charge at the oxygen end and a slight positive charge at the hydrogen end.

• Hydrogen Bonds
  Water molecules form weak bonds between the positively charged hydrogen of one molecule and the negatively charged oxygen of another, explaining many unique properties of water.

• Cohesion
  Water's molecules stick together due to hydrogen bonds, leading to surface tension that enables some organisms to walk on water.

• Adhesion
  Water molecules also adhere to other molecules with positive or negative charges, allowing for various interactions in biological contexts.

• Capillary Action
  Water can move against gravity from plant roots to leaves through small tubes due to cohesion (water molecules sticking to each other) and adhesion (water molecules sticking to tube surfaces).

• Universal Solvent
  Water can dissolve many charged compounds, such as salts and sugars. This property is crucial for biological systems, as it allows cells and blood to transport dissolved substances.

• Low Density of Solid Water
  When frozen, water expands, causing ice to float. This creates an insulating layer on frozen lakes, protecting ecosystems beneath the ice during winter and preventing lakes from freezing completely.

• High Specific Heat
  Water requires significant energy to change temperature because of the hydrogen bonds between its molecules. This property helps organisms maintain stable internal conditions (homeostasis) despite external temperature fluctuations.

• Neutral pH
  Water has a pH of 7, which is neutral. This stability is critical for cellular function, as extreme pH levels can damage cellular organelles.

• Surface Tension
  The cohesive forces at the surface of water create a "film," minimizing surface area and allowing various phenomena, such as the ability for small insects to walk on water.