Chapter 2 Flashcards
Matter
Anything that has mass (weight) and occupies space. It can be seen, smelled, and/or felt.
Wt = mass x gravity
Earth g= 1.0
Energy
Not physical, cannot be confined to a space and doesn’t have mass. It is the capacity to do work or put matter into motion.
Where in an atom are protons and neutrons found?
The nucleus
Where in an atom are electrons found?
They orbit around the nucleus (orbitals/shells).
Kinetic Energy
The energy of motion/movement.
Potential Energy
The energy of position or stored (inactive) energy. Can be converted into kinetic energy.
Temperature
A measure of the amount of kinetic energy in a substance. How fast molecules are moving.
Solid
Molecules fixed in space, relative to each other. Definite shape and volume.
Fluid
Molecules are in motion relative to each other. Both liquid and gas are both fluid.
Liquid
Molecules are in motion but are transiently (temporarily) bound to each other.
Gas
A substance with molecules in motion, but they are not bound to each other.
Chemical Energy
A form of potential energy. Energy is stored in bonds of chemical substances. Lipids, fats, carbohydrates, atp.
Electrical energy
Movement of molecules that have positive or negative charges on them.
Laws of thermodynamics
1.) energy cannot be created or destroyed in normal chemical reactions
2.) energy can be converted, but some is lost as heat
Protons
Carry a positive charge (+)
Weighs 1 atomic mass unit (amu)
Mass of motion=
= 1 amu
Neutrons
Has no electrical charge, and weighs 1 amu.
Electrons
Carries a negative charge (-)
Has very little weight, but not zero
Electrically neutral atoms (the same)
The number of positive protons is balanced by the number of negative neutrons which makes atoms electrically neutral.
Atomic Number
The number of protons in the nucleus.
Mass number
The total number of protons and neutrons in the nucleus.
Protons + Neutrons = Mass number
Solutions (definition)
A solute is dissolved in a solvent to form a solution. Solutions are homogeneous mixtures.
Solute
The substance being dissolved Ex.: Sugar
Solvent
The substance doing the dissolving. Ex.: tea
Water is the universal solvent
Solution
Solute + Solvent = Solution
Ex.: Sweet tea
(Sugar/Solute + Tea/Solvent = Sweet Tea/solution)
Avogadro’s Number
6.02 x 10^23
Molarity (M)
The number of moles of solute per liter of solvent (water).
Chemical Bonds
“energy relationships” between electrons of reacting atoms. Electrons are the subatomic particles involved in all chemical reactions. Protons and neutrons are NOT involved in chemical bonds.
Electron Shell #1
Can only hold 2 electrons
Electron Shell #2
Shell 2 holds a maximum of 8 electrons
Electron Shell #3
Shell 3 holds a maximum of 8 electrons.
Valence Shell
The outermost electron shell. The electrons in this shell are the ones involved in determining chemical bonding.
What are electrons in the valence shell called?
Valence electrons
Octet rule (rule of eights)
Most atoms desire 8 electrons in their valence shell. Exceptions are smaller atoms such as H and He. The desire to have 8 electrons is the driving force behind chemical reactions.
Inert
Doesn’t have to interact with other elements because it is already stable. Example are the noble gases.
Nobility
Noble elements that only interact with themselves.
Electronegativity
The measure of how selfish and greedy an atom is for electrons (e-).
Ionic Bond
Electrons are completely exchanged or transferred.
Covalent Bonds
Sharing 2 or more valence shell electrons between 2 atoms.
What are the 2 types of covalent bonds?
Polar and nonpolar covalent bonds
Exergonic
Reactions release or give off energy.
Endergonic
Reactions absorb or use up energy.
Hemoglobin F
Has a higher affinity for oxygen. “Fetal hemoglobin” is found in fetuses only.
Hemoglobin A
Found in adults. We start developing hemoglobin A as we grow.
Adenine (A) Links with?
Thymine (T)
Thymine (T) links with?
Adenine (A)
Cytosine (C) links with?
Guanine (G)
Guanine (G) links with?
Cytosine (C)
Which nucleotide is only found in DNA?
Thymine (T)
Which nucleotide is only found in RNA?
Uracil (U)
What did Erwin Chargaff discover?
%A = %T and %C = %G
What does DNA stand for?
Deoxyribonucleic acid
What does RNA stand for?
Ribonucleic Acid
What are nucleic acid polymers made up of?
Monomers called nucleotides
What are nucleotides composed of?
A nitrogenous base, a pentose sugar (either ribose for RNA or deoxyribose for DNA), and a phosphate group.
ALL proteins are made from how many different types of amino acids?
20 types of amino acids
If something ends in -ase it is a…
Enzyme
If something ends in -ose it is a…
Carbohydrate
What is a pentose?
5 carbon sugar
What is triose?
3 carbon sugar
Blood pH of a normal, healthy person
7.4
Blood pH range
7.35 ——- 7.4 ——- 7.45
(Acidic) (Normal) (Alkaline)
What are the polymers of glucose?
Starch and glycogen.
pH measures what?
Hydrogen (H^+)
Which molecule is used by all animals as long-term storage?
Triglycerides
Which molecule is used by all animals as medium-term storage?
Glycogen
Which molecule is used by all animals as short-term storage?
Glucose
What do catalysts do?
Catalysts increase the rate of reaction without being chemically changed or becoming apart of the product.
What is an example of a biological catalyst?
Enzymes
What is an acid?
A substance that will donate a H+ (hydrogen ion) when placed in an aqueous solution.
What is a base?
A substance that will take up a H+ (hydrogen ion) when placed in an aqueous solution.
What are buffers?
They resist abrupt and large swings in pH.
When pH rises (alkaline), what do buffers release?
They can release H+ (hydrogen ions)
When pH falls (acidic), what do buffers do?
They can bind H+ (hydrogen ions)
What is the difference between ionic bonds and covalent bonds?
Ionic bonds completely transfer electrons. Covalent bonds share electrons, either equally (non-polar) or unequally (polar).
What do negative catalysts do?
They can slow down a reaction without being consumed or becoming apart of the product.