Chap 5 Flashcards
whats the density of water
1 g cm3
does water have a high surface tension or low surface tension
high
what is surface tension
a result of cohesive force betweeen the molecules of water at the surface that allows various things to float to water
meaning of capillary action
cohesive force between water molecules n adhesive force between water molecules and cell walls of xylem which allow water to be drawn up from the roots to leaves.
what results in the change of water?
absorption and release of heat
water is a compound made out from :
hydrogen and oxygen that combine chemically
how can we determine the composition elements in a water molecule
through electrolysis
during electrolysis , oxygen gas is produced at the _______ while hydrogen gas is produced at the ___________
anode, cathode
whats an anode
the electrode that is connected to the positive terminal of a battery
whats a cathode
the electrode that is connected to the negative terminal of a battery
what is salt’s effect on ice and water
- lowers melting point of ice
- increases boiling point of water
What is evaporation
the process that happens at the surface of water that changes water to water vapour
what are the 4 factors that affect the rate of evaporation of water
humidity, surrounding temp, exposed surface area of water, movement of air
how does humidity affect the rate of evaporation of water
- dry air contains less water vapour and therefore can hold more water molecules that escape from the surface of water
how does surrounding temp affect the rate of evaporation of water
- when surrounding temp increase, the water molecules at the surface gain more energy, move faster n escape into the air easily.
how does exposed surface area of water affect the rate of evaporation of water
exposed surface area that is larger allows more water molecules to escape
how does movement of air affect the rate of evaporation of water
-sweeps away water vapour in the air
- high speeds of wind cause the air at the surface of water to dry
whats a solute
substance that can dissolve in a liquid
whats a solvent
liquid that dissolves a substance
whats a solution
mixture formed when a solute dissolves in a solvent
Solutions formed can be classified as: (3)
dilute solution, concentrated solution and saturated solution
Characteristics of Dilute solution
-less amount of solute in the solvent
- can dissolve more solute
Characteristics of concentrated solution
-more amount of solute in the solvent
-can dissolve less solute
characteristics of saturated solution
-excess amount of solute in the solvent
- cannot dissolve any more solute and form precipitate
difference between solution n suspension
solution is a clear mixture formed when a solute dissolves in a solvent
suspension is a cloudy mixture formed from undissolved solute particles in a solvent
What is Solubility
Solubility of a solute is the maximum amount of the solute that can dissolve in the solvent at a specific temp
what affects the rate of solubility
high temperature, rate of stirring and size of solute
why does the size of solute affect the rate of solubility
the smaller the size of solute, the bigger the total surface area that is exposed to the solvent particles
whats a colloid
a mixture of two or more solutes dispersed evenly in a solvent, it is an intermediate between a solution and a suspension
why is water known as a universal solvent
due to its ability to dissolve almost all substances, solids,liquids or gases
What are the 5 categories of organic solvents
alcohol
kerosene
acetone
turpentine
ether
whats the use of organic solvents
can be used to dissolve solutes that are insoluble in water
what r the 4 water purification methods
boiling, chlorination, filtration, distillation
