biochem study guide p2

What is a proton?

Positively charged, heavy subatomic particle.

What are the characteristics of a proton?

Positively charged, heavy, stays stable, weighs 1 amu, determines an atom's characteristics.

What is a neutron?

Neutral charge, heavy subatomic particle.

What are the characteristics of a neutron?

Neutral charge, heavy, weighs 1 amu, determines an atom's stability.

What is an electron?

Negatively charged, light subatomic particle.

What are the characteristics of an electron?

Negatively charged, light, responsible for 'interesting chemical stuff', weighs ~0 amu, determines an atom's reactivity.

What is the nuclear force?

Force that holds the nucleus of an atom together.

What is atomic mass?

Average mass of all the isotopes of an element.

What does the chemical symbol represent?

The element's name and atomic number.

How did the discovery of subatomic particles impact atomic theory?

Revolutionized atomic theory.

What is the significance of subatomic particle research?

Continued expansion with new discoveries and advancements in technology.

Why is understanding the behavior of subatomic particles important?

Essential for many areas of science, including nuclear physics and chemistry.

What is the level of organization from atoms to organs?

atoms → molecules → cells → organs

How does energy flow in an ecosystem?

It enters and exits

What happens to chemicals in an ecosystem?

They cycle, being used and recycled

What is natural selection?

Individuals better suited to an environment survive and adapt

What is a compound?

A substance with two or more elements combined in a fixed ratio

What are the characteristics of a compound?

It has different chemical and physical characteristics from its constituent elements

What are essential elements?

Elements needed for a healthy life

What is an example of an essential element for vertebrates?

Iodine (I)

What does water provide in the human body?

A high percentage of oxygen

What are the parts of an atom?

Protons, neutrons, and electrons

What is the mass number of an atom?

The sum of protons and neutrons

What is the atomic number of an atom?

The number of protons

How do you calculate the number of neutrons in an atom?

Subtract the atomic number from the mass number

How many neutrons does hydrogen have?

None

What are isotopes?

Atoms with different numbers of neutrons

What is an example of a common isotope of carbon?

Carbon-12, which accounts for 99% of carbon in nature

What is kinetic energy?

Energy in motion

What is potential energy?

Energy that could become kinetic

How do covalent bonds form?

They form molecules

What happens to shared electrons in a covalent bond?

They are pulled towards the electronegative atom

What are ions?

Resulting oppositely charged atoms

What is an ionic bond?

The formation of ions, with a positive cation and a negative anion

How do atoms balance their charges in an ionic bond?

They share electrons

What are endorphins?

Signaling molecules that relieve pain and produce euphoria

Are all chemical reactions reversible?

Yes, all chemical reactions are technically reversible

What is chemical equilibrium?

The point when reactions offset each other exactly

What is unique about water?

It is the only element that exists as a solid, liquid, and gas

What is evaporation from leaves responsible for?

Pulling water upward from the roots through water-conducting cells.

What is cohesion of water?

The tendency of water molecules to stick together.

How does water's surface tension benefit the raft spider?

It allows the spider to walk on the surface of a pond.

What is thermal energy?

Kinetic energy associated with the random movement of atoms or molecules.

Define calorie.

Unit of heat to raise the temperature of 1 gram of water by 1 degree Celsius.

How many joules are in one calorie?

0.239 joules, one calorie is 4.184 joules.

What is the result of polar covalent bonds within water molecules?

Hydrogen bonding between water molecules.

Name four properties of water for Earth's sustainability for life.

Cohesive behavior, adhesive, capillary action, transpiration; ability to moderate temperature; expansion upon freezing; versatility as a solvent.

What happens when the oxygen atoms of two different water molecules come together?

They repel.

What happens when the hydrogen atoms of two different water molecules come together?

They repel.

What happens when an oxygen atom and a hydrogen atom from two different water molecules come together?

They attract.

Are atoms magnetic?

No, but the north and south poles can represent the partial positive and partial negative charges on a water molecule.

What causes hydrogen bonding between water molecules?

Polar covalent bonds within water.

What gives rise to the properties of water?

Attractions between oppositely charged atoms of different water molecules.

Why does water expand upon freezing?

Proper formations form with hydrogen bonds.

What is specific heat capacity?

The amount of energy required to raise the temperature of 1 gram of a liquid by 1 degree Celsius.

Why does water have a high specific heat?

More energy is required to heat it.

How does the high specific heat of water benefit living things?

It helps them maintain homeostasis by resisting major fluctuations in temperature.

What is homeostasis?

The property of life where an organism's internal conditions remain stable and relatively constant, such as pH and temperature.

What would happen if there was no cohesion in water?

Rain would not exist, and there would only be singular water molecules in the sky.

What happens when water ionizes?

It releases an equal number of hydrogen ions (H+) and hydroxide ions (OH-).

Do H+ ions exist on their own in an aqueous solution?

No.

What is dynamic equilibrium?

A highly reactive state.

What does a pH of 2 mean?

There are 10^-2 (0.1) moles of H+ ions in one liter of water.

What is a mole?

A unit used to equal 6.02 x 10^23 molecules.

What is the formula for pH?

pH = - log [H+].

What does pH represent?

The amount of hydrogen or hydronium ions in a solution.

What does an acid do?

Donates H+ ions to a solution, increasing H+ concentration.

Give an example of an acid.

Hydrochloric acid (HCl).

What happens when HCl disassociates in an aqueous solution?

There will be an increase in the number of H+ ions.

What happens with bases?

They accept H+ ions.

What is the difference between strong and weak acids/bases?

Strong acids or bases completely disassociate, while weak acids or bases can reversibly release and accept back hydrogen or hydroxide ions.

What is the internal pH of most living cells?

Close to 7.

What is the pH of human blood?

7.4.

What happens if there are deviations in blood pH?

It can lead to death in a few minutes.

What happens when 0.1 mol of a strong acid is added to water?

pH drops from 7 to 2.

What happens when 0.1 mol of a strong acid is added to blood?

pH drops from 7.4 to 7.3.

What is a buffer?

A substance that minimizes changes in the concentrations of H+ and OH- in a solution.

What does a buffer do?

It accepts hydrogen ions from the solution when they are in excess and donates hydrogen ions when they are depleted.

What is bicarbonate?

A byproduct of metabolism.

What is organic chemistry?

The scientific study of the structure, properties, and reactions of organic compounds.

What are the four main atoms in organic molecules?

Hydrogen, Oxygen, Nitrogen, Carbon

What is a tetrahedron?

A triangular pyramid

What happens when tetrahedrons overlap?

They form a plane, which is a flat molecule

What factors are considered when drawing organic molecules?

Length, branching, double bond position, presence of rings

What are the three types of multiple bonds in hydrocarbon chains?

Single (alkane), double (alkene), triple (alkyne)

What are isomers?

Compounds that have the same numbers of atoms of the same elements but different structures and properties

What are functional groups?

Groups attached to carbon chains that determine how the molecule will behave

What are some examples of functional groups?

Hydroxyl group (OH), Carbonyl group (CO), Carboxyl group (COOH), Amino group (NH2 or NH3), Sulfhydryl group (SH), Phosphate group (PO3), Methyl group (CH3), Ether group (CO), Ester group (COOC)

What are isomers?

Variation in the architecture of organic molecules

What are structural isomers?

Isomers with different covalent arrangements

What are cis-trans isomers?

Isomers with different arrangements about a double bond

What are enantiomers?

Isomers with different spatial arrangements around an asymmetric carbon (mirror image molecules)

How does shape impact processes?

Shape influences various chemical and biological processes

What is a tetrahedron?

Simple organic can be tetrahedrons.

How is carbon bonded in a tetrahedron?

Carbon bonded to four other atoms.

What is the relationship between unpaired electrons and valence?

The number of unpaired electrons in the valence shell of an atom is generally equal to the atom's valence.

Which elements are most frequently bonded to carbon?

Hydrogen, Oxygen, Nitrogen.

What are carbon chains?

Skeletons of most organic molecules, can have double bonds and vary in length.

What are hydrocarbons?

Organic molecules consisting of only carbon and hydrogen.

Where are hydrocarbons commonly found?

Major component of petroleum (fossil fuel).