Ch 2. BIO101A - Chemistry

matter

anything that occupies space and has mass

element

pure substance that cannot be broken down → simpler substances by chemical/physical techniques

an element that occurs in organisms in very small quantities

trace element

atoms

the smallest units that retain chemical/physical properties of an element

compound

molecule made of fixed ratio of two/more different elements

What is inside the atomic nucleus?

Protons + Neutrons

Where are electrons located?

Orbital paths around atomic nucleus

a distinct form of atoms of an element, with same number of protons, but different number of neutrons

isotope

isotopes have same atomic number but…

different mass number

mass

amount of matter in an object

weight

measure of pull of gravity on an object

giving off of particles of matter and energy by decaying nuclei

radioactivity

radiometric dating

uses clockwork decay of unstable isotopes to age organic material, rocks, fossils

The number of electrons surrounding the nucleus equals the

number of protons in the nucleus

orbital

region of space where electron lives most of the time

1s orbital is in the…

nucleus

1s orbital fits..

2e

2p fits

6 e

3d fits

10 electrons

an electron in outermost energy level of an atom

valence electrons

atoms in outermost energy level that is not filled are…

chemically reactive

completely filled outermost energy levels are…

nonreactive/inert

chemical bonds

link formed when atoms of reactive elements join into molecules

two or more atoms held together by chemical bonds is called a

molecule

ionic bonds

electrical attractions between atoms that gain/lose valence electrons completely

i.e: NaCl

a positively charged ion like Na+ is a…

cation

a negatively charged ion sub as Cl- is an

anion

True or false: Chemical bond exert an attractive force greater distances than any ionic bond

F, vice versa

Bond formed by electron sharing between atoms

Covalent bonds

the measure of tendency of an atom to attract electrons to itself in a chemical bond (to become negative)

electronegativity

non polar covalent bond

electrons are shared equally/nearly equally;

atoms involved have no charge

polar covalent bond

atom attract electrons more strongly → has a partial negative charge, (Δ-),

atom deprived of electrons has a partial positive Δ+

polar associations

when polar molecules align themselves with other polar molecules and with charged ions & molecules

nonpolar associations

association that occurs when non polar molecules clump together

intermolecular

between atoms in different molecules

intramolecular

between atoms in the same molecule

Hydrogen bonds are easier to break than covalent and ionic bonds.

True

Van der Waals forces

Weak molecular forces over short distances

How does an ionic bond form?

An ionic bond forms between atoms when those atoms gain or lose electrons completely.

How does a covalent bond form?

A covalent bond forms when atoms share a pair of valence electrons rather than ganing/losing completely

What is a chemical reaction?

atoms/molecules interact to form new bonds/break old ones

atoms are added/removed → molecules, linkages of atoms are rearranged

water lattice

an arrangement formed when. water molecule in liquid water establishes an avg of 3.4 H bonds with its neighbors

ice lattice

spaces water molecules farther apart than water lattice

the amount of energy as heat required to increase temperature of a given quantity of water

specific heat

calorie

amount of heat energy required to raise 1g of water by 1c

heat of vaporization

allows humans & many other organisms to cool when hot

cohesion

the high resistance of water molecules to separation (via hydrogen bond lattice)

molecules stick to walls of tube forming H bonds w/ polar groups in tubes

adhesion

surface tension

force places surface water molecules under tension → making them more resistant to separation than underlying water molecules

hydration layer

surface coat of water molecules,

covers other polar & charged molecules/ions

The number of moles of a substance dissolved in 1 L of solution is known as the

molarity

solution

solute dissolved in a solvent

bases

proton acceptors that reduce H+ [] of a solution

buffers

substances that compensate for pH changes by absorbing/releasing H+

acids

hydrogen ion (proton H+) donors

bases

H+ acceptors

acid dissociates → water to produce

H+ ion and atom

most bases dissociate in water to

give OH- ions → which accept protons → H2O

emergent properties

trait/characteristic possessed by object due to arrangement/interaction of components

not found in components themselves

emergent property of life #1

increase in size/cell no.

systematic change in form / function over time

energy utilization to do useful work

sun → radiant energy →

chemical energy

unicellular →

bacteria

multicellular

plants, animals

solar energy → chemical energy

photoautotrophs (plants)

humans are

heterotrophs

all (heterotroph) organisms perform…

cellular respiration, while plants do at night

Change in sate → receptor/detector →

___________ → effector → __________________

control center

response restores state

reproduction

generation of new, separate individual

_________ has information, blueprint for making new individual

hereditary system

change in form, structure, function of organisms over geologic time

evolve

atoms → molecules → ____________ → _____________ → organelles → cells → ____________ → organs → organ systems

macromolecules

supramolecular systems

tissues

how many bonds for O to complete outer shell (valence e)

2 bonds

how many bonds for N to complete outer shell (valence e)

3

how many bonds for C to complete outer shell (valence e)

4

how many bonds for P to complete outer shell (valence e)

3,5

Adaptation & natural selection are up to chance

F

Organelles are considered ‘alive’

F

How do viruses live?

Acellular, no metabolism, reproduction, invade host

How many protons in Carbon?

How many shells are filled?

How much electrons in first and second shell?

6 protons

1s2 2s2 2p2

How many protons are in Hydrogen?

How many shells are filled?

How much electrons in first and second shell?

1

1s1

How many protons in Oxygen?

How many shells are filled?

How much electrons in first and second shell?

8 protons

1s2 2s2 2p4

How many protons in Nitrogen?

How many shells are filled?

How much electrons in first and second shell?

7 protons

1s2 2s2 2p5

cells within the body communicate with each other using chemicals known as

receptors/proteins

Electrical attraction of partially (+) charged H on one polar molecule to partially (-) charged atom on 2^nd polar molecule

Hydrogen bond

Water has a lower structural organization than most other liquids

F, higher

ionic bonds exert forces in all directions

T

ionic bonds are all the same strength depending on charged substances

F, can vary

Of 92 elements, ______ found in organisms

25

biomolecules

carbon backbone

acts as an organic base accepting H+ in [aq] -> converting from a non-ionized to an ionized form

Amines

an _________ has the carbonyl group at the end of a carbon chain, bonded to a hydrogen atom,

while a ________ has the carbonyl group bonded to two other carbon atoms within the chain.

aldehyde (C1)

ketone (C2)

________________ give organic molecules acidic properties because -OH group releases H+ in [aq] converting from non-ionized -> ionized form

carboxylic acids

Thiols lose a hydrogen atom as it bonds

T

Methyl Group

Acetyl Group

same structures, different covalent molecular arrangement

isomer

L-form is biologically active while D-form is not

T

Lipids are made of building blocks, and are considered polymers

F, not polymers

Constructed by forming covalent bonds between basic building blocks

Macromolecules

Dehydration reaction:

Releases or requires energy?

Requires