2.2 - Properties of Waters Flashcards
What is a hydrogen bond?
A weak chemical attraction between polar molecules between a partial positive charge and a partial negative charge
A molecule in which the charges are evenly distributed is said to be what?
Polar because a molecule is a bit like a magnet with two poles A positive end and a negative end
How much of your body is water?
70% or 2/3 of molecules
Why is water so important for life?
Water stores heat efficiently, water helps cells maintain temperature by sweating, water bonds easily to it self and other substances
What is cohesion?
It is an attraction between substances of the same kind caused by the hydrogen bond
What causes surface tension?
Cohesion
Why can an insect walk on water?
Cohesion/surface tension
What is adhesion?
The attraction between different substances
What does surface tension prevent?
Prevents the surface of water from stretching or breaking easily
What is capillary action?
Is when one of the forces draws water out of the roots of a plant and up into stems and leaves
What powers capillary action?
Adhesion.
Waters heat capacity the amount of heat energy required to increase his temperature is relatively high or low?
High
What is a mixture?
It is a material composed of two or more elements or compounds that are physically mixed together but not chemically combined
What are two types of mixtures that can be made with water?
Solutions and suspensions
What is a solution?
Mixture of one or more substances that is evenly distributed in another substance
What is a solute?
The substance that is dissolved
What is a solvent?
The substance in which the solute dissolves
Waters player that he gives it to ability to dissolve what?
Both ionic compounds and other polar molecules
In salt water what is the solute?
The salt
In salt water what is the solvent?
The water
Do nonpolar molecules dissolve well in water?
No
When an amount of water has dissolved all the salute it can it is said to be what?
Saturated
What are suspensions?
Mixture of water and non-dissolved materials
What is the pH scale?
The measurement system used to indicate the concentration of H positive ions in solution
What is the pH scale ranges
0 to 14
What is pure waters pH number?
Seven
Solution with a pH below seven are called what?
Acidic because they have more H positive ions than OH negative ions
What is a solution with a pH above seven called?
Basic because they have more OH negative ions than H positive ions
What is an acid?
A compound that forms H positive ions in a solution when dissolved in water
What is a base?
A compound that produces OH negative ions in the solution when dissolved in water
What is a example of a strong base?
Lye commonly used in soap making
