Water
True or False:
Buffers prevent any change in pH
False - they resist pH changes
What is the pH if [H+] = 1x10 ^ -4 M
pH = 4
Why is carbon important to living organisms?
It forms the structural backbone of organic molecules
How many single bonds can a carbon atom form?
4
What makes up a hydrocarbon?
Hydrogen and Carbon only
Adhesion - clinging of one substance to another by means of hydrogen bonds
Cohesion - linking together of the same molecules by hydrogen bonds
If [H+] increases, what happens to pH?
It decreases
What is an isomer?
Two molecules with the same molecular formula but different structures and properties
How many double bonds can a Carbon make?
2
What functional group is represented by -OH
Hydroxyl
2. Polar Covalent Bonds definition
3. What do they have in common
- electronegative : an atom that the electrons spend more time near
- polar covalent bonds : electrons are not shared equally
- both are properties of water
What do acids do to pH
They are solutes that reduce the pH (increase the [H+])
Structural isomers vs. cis-trans isomers
structural isomers : differ in covalent arrangements
cis-trans isomers : differ in spatial arrangement around a double bond
What is an enantiomer?
mirror images of each other; different arrangement in space
Why are hydrocarbons generally hydrophobic?
carbon-hydrogen bonds are typically nonpolar
A lake has a lot of water, but its temperature doesn't change as quickly as the surrounding land. Why?
Water has a high specific heat, so it resists temperature changes
What is the pH if the [OH-] = 1 x 10-11
pH = 3
Explain valence
# of unpaired electrons of a given atom
- the number of covalent bonds an element can form with atoms in a molecule (each unpaired e- can pair)
What is a characteristic of a phosphate function group
-PO42-
- very negative charge
What is a functional group?
Groups of atoms involved in chemical reactions that give organic molecules specific properties
What is the process of ocean acidification?
1. CO2 reacts with H2O to make H2CO3 (carbonic acid - lowers the pH)
2. H2CO3 breaks down into H+ and CO32-
3. The H+ binds to the available CO32- (carbonate) in ocean, but marine life needs the CO32- to make calcium carbonate (CaCO3) for coral and shells
How many times greater is the H+ concentration at Ph 2 than pH 4?
100x greater
What is a carbonyl group
found in sugars
- ketone (bound to 2 carbons)
- aldehyde (bound to a H)
What are some characteristics of amino functional groups
- NH2
- acts as a weak base (can accept H+)
- in amino acids
Is carbon versatile to bond to? Explain
Yes - lots of options for bonding
- can form 4 single bonds
- can form 2 double bonds
- can form 1 triple bond