2.1 Introducing chemistry for biologists Flashcards
What is matter?
Anything that has mass and takes up space, its made of tiny particles called atoms
What are atoms made of?
Protons Neutrons and electrons
What is a Bohr diagram?
Are simple models that represent the arrangement of the subatomic particles in an atom.
Electrons are more stable when they are at a__________
lower energy which occurs when they are closer to the nucleus
What is a molecule?
The bonding between atoms results
Why is it called intramolecular>
Bonds occurring within the molecule
What are the three types of intramolecular?
Ionic bonds
Covalent bonds
Polar covalent bond
What is polar covalent bonds?
Is an unequal sharing of valence electrons between atoms in the pair
Why is it called dipole?
Because one end is slightly positive and the other is slightly negative
Which one becomes more negative in a dipole
The one that pulls hardest on the electron this is because atoms differ in their ability to attract electrons
What is electronegativity?
Is the measure of an atom’s ability to attract electrons in a chemical bond
What are three types of intermolecular bonds?
- London forces
- Dipole-dipole forces
- Hydrogen bonds
oWhat are londong forces?>
Holds non-poplar molecules together
Very weak
Momentary dipoles are created by the electrons contained withing the compound which are moving
What are dipole-dipole forces?
Holds polar molecules together
What are dipole-dipole forces?
Holds polar molecules together
Stronger than london
What is a hydrogen bonding?
formed between the electropositive hydrogen dipole and electronegative dipole
strongest
Explain the polar covalent nature of the water molecule.
The oxygen in a water molecule is more electronegative than hydrogen so a dipole is formed with an area that is more negative, near the oxygen and an area that is more positive, near the hydrogen atom.
What is hydrolysis?
When water helps break down molecules
Protein + water –>
amino acid +amino acid (hydrolysis)
What is condesation?
Condensation reactions occur when two molecules combine to form one molecule
What is condensation also known as?
Dehydration as water is produced.
When does condesation reaction occur>
when you’re building muscle tissue
The process of losing electrons is called
oxidation
The process of gaining electrons is called
reduction
The transfer of electrons from glucose helps the cell to make
high energy molecules
(ATP)
What is Neutralization?
Is the reaction of an acid and a base to produce water and a salt
What is Ionization?
Is the dissociation of a molecule into ions
Common properties of acids
Sour
Conducts electricity
Turns litmus paper red
pH below 7
What are buffers?
Are solution that are able to maintain nearly constant pH levels by removing the hydroxide ion and hydrogen
Include some examples of acid-base buffers
proteins
amino acids
carbonic acid
What is a carbonic acid-bicarbonate buffer?
Is a buffer that operates both in the blood and extracellular fluid to maintain a pH of 7.4. It contains both an acid and a base so it can neutralize conditions that are either too acidic or too basic.
How is the carbonic acid-base acid formed?
water + carbon –> H2CO3 <–> HCO3 - + H+
