Important Chemicals Pt. 1 Flashcards
What do organisms consist of?
Matter, Elements, and Atoms
The elements that comprise 96% of living matter are_____
Carbon, Hydrogen, Nitrogen, Oxygen (CHNO)
What makes up matter?
Elements
What makes up elements?
Atoms
What two characteristics form the atom?
Atomic nucleus & electron shell
What are the subatomic particles within atoms?
Protons, Neutrons, and Electrons
The number of ______ = the number of ________
of protons = # of electrons
List the charges of Neutrons, Protons, and Electrons
Neutrons = no charge
Protons = positive charge
Electrons = negative charge
Which particle defines the element (atomic number)?
The number of protons
When an element has the same number of protons, but a different amount of neutrons it’s called an _____. Which can be ________ is unstable
isotope; radioactive
An atoms nucleus contains….
Protons and Neutrons
What determines the reactivity of the atom?
Number of electrons
What is the outermost shell called?
Valence shell
What’s the rule of eights?
Atoms interact in a a way that they end up having 8 electrons in their valence shell
Inert is when an atom….
has a filled valence shell
If an atoms has an unfilled valence shell it is…..
Chemically reactive
What are the 3 types of bonds?
- Covalent
- Ionic
- Hydrogen
The most important determinant of an atom’s bonding behavior is _____
the number of valence shell electrons
Covalent bonds are when atoms ____ ____
share electrons
What are the 3 types of covalent bonds? Briefly describe each
Single: share 1 electron
Double: share 2 electrons
Triple: share 3 electrons
What is electronegativity?
The likelihood of an atom to attract shared elecrons
The higher the electronegativity, the more an atom will ….
pull shared electrons (pulls elements toward themselves)
Which two necessary elements have high electronegativities?
O and N
The equal sharing of electrons makes atoms _____
nonpolar
The unequal sharing of electrons makes atoms____
polar
Ionic bonds are the…
attraction of opposite charges
Nonpolar is the …
equal sharing of electrons
Polar is the….
unequal sharing of electrons
True or False
Ions with opposite charges are attracted to each other
TRUE
Which bond type is strong, but break in water
Ionic
The more electronegative atom will do what to the other atom within the bond?
Strip an electron away from the other atom
Hydrogen bonds are the..
attraction of hydrogen to an electronegative atom
Which bond type is very weak but very important? What’s an example?
Hydrogen Bonds (DNA)
Covalent bonds occur when …
a) electrons are shared between atoms
b) electrons are transferred between atoms
c) electrons are lost
d) opposite charges attract atoms together
A; electrons are shared between atoms
Ionic bonds connect atoms together by…
a) overlap of valence shells
b) charge attractions
c) overlap of the nucleus
d) attractions between dipoles
B; charge attractions
Which molecule is a universal solvent
water
What property does water have that makes it so important? Hint: bonding
Water’s polar –> the hydrogen in water bonds with other molecules, including other water molecules
____ increases hydrogen ion concentration of a solution
Acid
_____ decreases the hydrogen ion concentration of a solution
Base
Acids and Bases:
Which is the Donor and which is the Acceptor?
Acids are the Donors while Bases are the Acceptors
In terms of pH, which number is the most acidic, most basic, and neutral
most acidic = 0
most basic = 14
Neutral = 7
pH expresses the concentration of what?
H+ (hydrogen)
10^-7 moles is what pH?
7
A substance that is very acidic may have a pH of 1 or 2. This means that the acidic substance…
a) has a high concentration of H+ ions
or
b) has a low concentration of H+ ions
A; A pH of 1 or 2 means the substance has a high concentration of H+ ions
What are two locations where you’ll find buffers?
Blood plasma and Lungs
What are buffers?
Chemical systems that help maintain the homeostasis of the acid-base balance (maintain pH)
Buffers do what in response to a rise in pH?
Can release hydrogen ions
Buffers do what in response to a fall in pH?
Can bind hydrogen ions
Acids decrease pH which increases what?
increases hydrogen ion concentration
Bases increase pH which decreases what?
decreases hydrogen ion concentration
Why is carbon important?
Can form 4 covalent bonds and can form large, complex, and diverse molecules
What are the 4 macromolecules?
- Carbohydrates
- Lipids/Triglycerides
- Proteins
- Nucleic Acids
Another name for “building block” is what?
monomer
A polymer is made out of what?
Monomers
Polymers are synthesized by what?
Dehydration synthesis
Polymers are broken down by what?
Hydrolysis
Hydrophilic is what? Hydrophobic is what?
Hydrophilic is ‘water-loving’
Hydrophobic is ‘water-fearing’
Amphipathic means what?
A molecule is both hydrophobic AND hydrophilic
Hydrophobic molecules form what in water?
Droplets
Carbohydrates are a ___ and _______ _______
fuel and building material
Carbohydrates come in 3 sizes. Name them and briefly describe each
- Monosaccharide –> monomer
- Disaccharide –> 2 monosaccharides linked together
- Polysaccharides –> hundreds or thousands of monosaccharides linked together
Carbohydrates perform a wide variety of functions. Name 4
Provide energy
Energy Storage
Support
Structure
Glycosidic linkage describes….
monosaccharides joined by dehydration synthesis
What are two examples of Disaccharides?
Sucrose (plants) and Lactose (milk)
