chapter 2 Flashcards
Matter
Has mass and take space can be seen, smelled, or felt
Energy
Is the capacity to do work or put matter to motion. Does not have mass, no space.
Kinetic / potential
Kinetic- action
Potential- stored inactive energy
Forms of energy
Chemical
Electrical
Mechanical
Radiant
Chemical
Stores in bonds of chemical sub
Electrical
Movement of charged particles
Mechanical
Directly in moving matter
Radiant
Travels in waves (ex: heat, x rays, visible light)
Atomic number
off protons in nucleus
number of protons in nucleus
Isotopes
Structural vartiy of same element
Atomic weight
Average of mass # of all isotope forms of an atom
Mass number
Total number of protons and neutrons in nucleus
Four elements
OCHN make up 96% of body mass
O
65%
(Oxygen) used to generate ATP, a molecule
used by cells to temporarily store chemical energy.
C
(Carbon) 18%
Forms backbone chains and rings of all organic molecules: carbohydrates, lipids (fats), proteins, and nucleIc acids (DNA and RNA)
H
9.5%
(Hydrogen) A proton it influences the PH of body fluids.
N
(Nitrogen) proteins and nucleic acids
protons
positive charge (+) and weigh 1 amu (atomic mass unit)
Neutrons
have no charge (0) and weigh 1 amu
electrons
negative charge (-) are tiny they have no weight 0 amu
radioisotopes
are isotopes that decompose to more stable forms. (isotope decays, subatomic particles that are being given off release of radioactivity
molecules combing matter
2 or more atoms bonded together
Compound combing matter
specific molecule that has 2 or more different kinds of atoms share together
Mixture
combination of elements or compounds that are physically blended not bonded
3 types of mixture
- Solutions
- Colloids
- suspensions
Chemical Bonds
Occurs when atoms are held together by forces of attraction
3 bonds
- Ionic
- Covalent
- Hydrogen
Anion
negative (-) atom gained one or more electrons -
Ion
an atom that has lost or gained an electron
Cation
positive (+) atom lost one or more electrons
Covalent Bonds
When 2 or more atoms share electrons rather than donating/receiving
polar Cov bonds
unequal sharing of electrons between 2 atoms = electrically polar molecules
Nonpolar Cov bonds
equal share of electrons between atoms
Hydrogen bonds
Weak bonds that result from attraction of oppositely charges parts of molecules
Stabilize molecular structure of large molecules
chemical equations
occur when chemical bonds are formed, rearranged or broken
Reactions
starting sub
product
ending sub
Types of chemical reactions
Synthesis
Decomposition
Exchange
Oxidation-reduction
Synthesis (combination)
reacts atoms or molecules combining to form larger molecules, use anabolic (building)
A+B -> AB
Decomposition
breakdown of a molecule into smaller molecules. use catabolic (bond-breaking) reactions.
AB-> A +B
Exchange
bonds are both made and broken
π΄π΅+πΆ βπ΄πΆ+π΅
π΄π΅+πΆπ· βπ΄π·+πΆπ΅
reduction-oxidation
Atoms are reduced when they gain electrons and oxidized when they
lose electrons
Exergonic reactions
Release more energy than is consumes
Endergonic
Use more energy than it produces
Activation reaction
ensure more products will be formed, add energy
Catalysts
increase the rate of reaction without being chemically changed or becoming part of the product
Reversibility
All chemical reactions are theoretically reversible
π΄+π΅ βπ΄π΅