Chapter 2 The Chemical Context of life Flashcards
What is Matter?
What is matter made up of?
Anything that takes of space and has a mass.
Matter is made up of elements.
What is an element?
a substance that cannot be broken down to other substances by chemical reactions.
What is a compound?
A substance consisting of two or more different elements combined in a fixed ratio.
What are essential Elements?
Elements that lving things need to make us work.
What are the four elements that make up 96% of living matter?
What elements make up the other 4%?
who is CHON (96%)
- C = Carbon
- H = Hydrogen
- O = Oxygen
- N = Nitrogen
Hes the KCaPS of the orientals (4%)
- K = Potassium
- Ca = Calcium
- P = Phosphorus
- S = Sulfur
What are Trace Elements?
Are elements that a living organism needs but a very small amount.
What is an Atom?
What three particles make up an atom?
An Atom is the smallest unit of matter that still retains the properties of an element.
Smallest particle of an element that retains its properties.
The three particles that make up an atom are called subatomic particles.
- Neutrons (neutral)
- Protons (positive)
- Electrons (negative)
- atoms have a nucleus
- electrons and protons attract each other so atoms usually have the same number of protons and electrons
How many electrons are in the element Oxygen?
8 electrons
Atomic nucleus is? (what type of charges) and where is the nucleus located in an Atom?
What surrounds the Atoms nucleus and why?
An Atoms nucleus is in the center of the atom, its also a combinaton of Protons and Neutrons that are packed together tightly in a dense core.
The atoms nucleus is a positive charge.
Surrounding the atoms nucleus is rapidly moving electrons that form a “cloud” the cloud is negatively charged. since protons and electrons are attracted to one another, the electrons stay in the vicinity of the nucleus.
Dalton is used to measure what?
Atoms, subatomic particles and molecules.
Neutrons and protons equal 1 Dalton
What does indivisible mean in regards to atoms.
atoms can neither be created nor destroyed in a chemical reaction.
In a chemical reaction chemicals only get rearranged.
what is an Atomic number
the number of protons in one atom of an element.
is written a subscript to the left of the symbol for the element.
What is a mass number? what is the equation to find the mass number.
a combination of protons and neutrons in an atom
mass number = protons + neutrons
Atomic Mass
Mass of an Atom, which is a combination of its protons and neutrons.
the average mass number of an elements atom and its isotopes.
What are Isotopes?
A variation of an element. it contains a different number of protons than neutrons.
What is a half life when refering to an isotope?
When the “parent” isotope decays into its “daughter” isotope at a fixed rate.
half life is the time it takes for 50% of the isotope to decay.
What is Radiometric dating?
when scientist measure the ratio of different isotopes and calculate how many half-lives (In years) have passed since an organism was fossilized or a rock was formed.
What is energy (dealing with elements and atoms)
The capacity to cause change-for instance, by doing work.
What is Potential energy? give an example
The energy that matter possesses because of its location or structure.
energy of position further away from its resting state.
Example, water in a reservoir on a hill has potential energy because of its location or structure.
Electron shells name the four of them and amount of electrons that fit in each one
An electron shell is the outside part of an atom around the atomic nucleus. It is a group of atomic orbitals with the same value of the principal quantum number n. Electron shells have one or more electron subshells, or sublevels.
the path the electron is going in the orbitial
Suzan S 2 per shell
pukes P 6 per shell
dick D 10 per shell
forever F 14 per shell
What are Valence electrons and whats the name of the shell they are in?
are the electrons in the outermost shell and the name of that shell is the valence shell.
Elements with an incomplete valence shell are more likely to have chemical behavior.
if the valence shell is complete (full) the element is inert(chemicaly unreactive).