Chemistry of Life Flashcards
Matter
Anything with mass, occupies space, and is made of atoms
6 Elements necessary for life
CHONPS (Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, and Sulfur)
Atoms
Made of subatomic particles, has neutrons, electrons, and protons
Where are electrons found in an atom
Electron clouds and electron shells
Where are Neutrons and Protons found in an atom
In the nucleus
Cell
The most basic unit of life
Order of units of life
Atom, molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem, biome, biosphere
Atomic structure
Atoms are made of protons and neutrons in a nucleus and electrons in a surrounding electron cloud
Where is most of an atom’s mass
Positively charged nucleus
Where is most of an atom’s volume
Negatively charged electron cloud
In a periodic table, what does the atomic number tell you
Number of protons an element has
What is the average atom mass of an element from the nucleus
The sum of protons and neutrons in the most common isotope
Isotope
2 or more forms of the same element with different amounts of neutrons and is written as the elements name, then the mass number in the top left and atom number in the bottom left
How is the electron cloud of an atom divided
Into energy shells or levels; innermost shell can hold up to two electrons and most other can hold eight
Valence electrons
Electrons in the outermost shell of an atom
How many valence electrons does a noble gas have
8
Compound
Two or more atoms of different elements bound together
Molecule
Two or more atoms covalently bonded together
Covalent bonds
When non-metallic atoms share electrons
Ionic bonds
When electrons are transferred from a metallic atom to a non-metallic atom
Cation
When an atom loses electrons and becomes more positively charged
Anion
When an atom gains electrons and becomes more negatively charged
Single bond
One electron from each atom is shared
Double/triple bond
Two/three electrons from each atom is shared
Polar molecule
Unequal distribution of charges makes one side more positive and one side more negative, dissolves in water
Nonpolar molecule
No separation of charge, no negative or positive poles are formed
What is the attraction between polar molecules
Hydrogen bond
Which is stronger, hydrogen or covalent bonds
Covalent bonds
What does the group number tell you on the periodic table
Number of valence electrons an atom has
What does the period number tell you on the periodic table
How many energy levels an atom has (Energy levels are number of shells)
Water makes up how many percent of the human body
65%
what percent of the earth’s surface is covered in water
71%
Is water a polar or nonpolar molecule
Polar
What term explains water droplets being formed by water molecules attracted to each other
Cohesion
What property allows water to stick to the sides of a straw
Adhesion
What property of water allows bugs to walk on water
Surface tension
Amount of heat it takes water to change to its gaseous state
Large amounts
What property allows sweat to cool the body and coastal cities to have more moderate temperatures than inland cities
high heat capacity
A solution with a pH less than 7 is
Acidic
A solution with a pH more than 7 is
Basic
Why is water a polar molecule
The oxygen in water is slightly more electronegative than the oxygen
What bond occurs between hydrogen and oxygen atoms
Covalent bonds
What type of bond is formed between water molecules
Hydrogen bonds
Why does surface tension and capillary action occur in water
Because it has hydrogen bonds
What kinds of substance can dissolve in water
Polar molecules
What needs to be true for a neutral solution
H+ must equal OH-
What needs to be true for a basic solution
OH- needs to be greater than H+
What percent of water on earth is salt water
97%
Where is most fresh water found
Glaciers and ice caps
Evaporation
Liquid water on Earth’s surface changes into water vapor in the atmosphere
Sublimination
Snow or ice on Earth’s surface changes directly into water vapor in the atmosphere
Transpiration
Plants give off liquid water, most of which evaporates into the atmosphere
Condensation
Water vapor in the atmosphere changes to liquid water droplets, forming clouds or fog
Preipitaiton
Water droplets in clouds are pulled to Earth’s surface by gravity, forming rain, snow or other types of falling moisture
What are the freezing points of water
0 Degrees Celsius or 32 degrees Fahrenheit
What are the boiling points of water
100 Degrees Celsius or 212 degrees Fahrenheit
pH of water
7
Why is water colorless
Its selective absorption and scattering of white light (Transparency) allows sunlight to pass through it
Water is consisted of
One atom of oxygen, two atoms of hydrogen (H2O)
Why is water considered a universal solvent
Because it dissolves almost everything
Define solution
A homogeneous mixture composed of 2 or most substances
Define solute
A dissolved solution
Define solvent
The substance that is being dissolved
Define solubility
A solute’s ability to dissolve in a solvent
Define Hydrophilic
“Water liking” and easily dissolvable in it
Define Hydrophobic
“Water fearing” and does not dissolve in water
