3 Properties of Water Flashcards
All cellular processes occur in an _____ environment.
aqueous (water based)
The most abundant liquid on Earth is …
Water. It is a polar molecule that can form 4 hydrogen bonds with other H20 molecules.
What must happen for a liquid water molecule to escape as a vapor molecule when water is heated?
The water molecule must gain enough energy to break all surrounding intermolecular forces (IMFs).
What is specific heat capacity?
The amount of energy required to raise the temperature of 1 kg of a substance by 1°C.
Why does ice float in water?
Ice is less dense than water because water molecules spread out when they freeze, forming a crystalline lattice.
What happens to water molecules when water freezes?
They spread out into a repeating crystalline structure (lattice), making ice less dense than water.
How does ice formation on the surface of water benefit aquatic life?
Ice insulates and protects aquatic life by maintaining temperatures below freezing under the ice.
What is cohesion, and how does it affect water?
Cohesion is the attraction between particles of the same substance. Water is highly cohesive due to its ability to form 4 hydrogen bonds, resulting in high surface tension.
What is adhesion?
Adhesion is the attraction between particles of different substances.
Why can water move up the stem of a plant?
Water moves up a plant stem due to capillary action, which occurs because water is both adhesive and cohesive.
What is a hydration shell?
It is a layer of water molecules that surrounds an ion or polar molecule when placed in water.
How do ionic crystals dissociate in water?
Water molecules form dipole-ion intermolecular forces with the ions, creating hydration shells and splitting the crystal into smaller pieces.
What is an acid, and how does it behave in water?
An acid increases the concentration of H₃O⁺ ions in water. Acids often contain ionizable hydrogen (H⁺) in their chemical structure.
What is a base, and how does it behave in water?
A base increases the concentration of OH⁻ ions in water.
What does pH measure?
pH measures the concentration of H⁺ ions in a solution. Pure water at 25°C has equal concentrations of H⁺ and OH⁻ and a neutral pH of 7.
What is the pH scale, and what do the values indicate?
The pH scale measures acidity and basicity. A pH of 7 is neutral, pH < 7 is acidic, and pH > 7 is basic.
