How does the Flounder survive in New England? Part 1 Flashcards
What is Life composed of?
Matter
What 2 forms of matter are elements?
Special chemical properties
Special physical properties
How many elements are there?
- 98 occur naturally and 20 are manmade.
What is the basic structure of an Atom?
It has a nucleus with 2 regions being the Protons and Neutrons. It also has Electron Shells with electrons.
What are protons and neutrons?
Protons are positively charged and Neutrons are neutral charged
What are electrons?
Electrons are negatively charged
What is an Atomic Number?
The number of protons
What is the Mass Number?
The number of both protons and neutrons
What is the Atomic Mass?
Mean of mass number of naturally occurring isotopes; which is roughly equal to no. of protons and neutrons.
What is variably changes to create Isotopes?
Neutrons
What is an Isotope?
Different forms of an element with the same number of protons but a different number of neutrons and different masses.
How many Electrons are there in an atom?
The number of electrons is the same as the number of protons and thus same as atomic number.
What is the model of an atom called?
The Bohr model
How do electrons fill electron shells?
They use the Octet Rule which states that with the exception of the innermost shell, that atoms are more stable with 8 electrons in their valence shell
What is a Valence Shell?
The Outermost Shell and determines the energy level and stability and tendency to from bonds with other atoms
What are Orbits?
The movement around the nucleus in specific regions and are classified with subshells as ‘s’, ‘p’, ‘d’ or ‘f’ and numbers of shells as ‘n’
What are molecules?
Atoms bonded together
What is Electron Transfer??
The satisfying of the octet rule when atoms gain or lose an electron
What are Cations and Anions?
Cations are positive ions that form by losing electrons.
Anions are negative ions that form by gaining electrons.
What are Ionic Bonds?
Bonds formed between the opposite charged atoms
What are Covalent Bonds?
The sharing of electrons with single, double or triple bonds and are stronger than ionic bonds
What are Polar Covalent Bonds?
When atoms unevenly share the electron and are attracted to one nucleus than the other due to unequal distribution between atoms creating a slightly positive or negative sharge
Is a water molecule polar or non-polar?
It is a polar molecule as the oxygen atoms nucleus is more attractive to the hydrogen atoms electrons than the hydrogen nucleus is to the oxygens electrons
What is Electronegativity?
Strength with which atoms pull electrons toward themselves
What is Electronegativity determined by?
- Number of Protons
- Distance of valence shell from nucleus.
Other ways to explain Polar Covalent Bonds
Electrons spend more time near the oxygen nucleus than the hydrogen atoms nucleus.
OR:
The probability of finding shared electron near an oxygen nucleus is more likely than finding it near a hydrogen nucleus.
What are Non-Polar Covalent Bonds?
When atoms evenly share electrons and the bond is symmetrical
Why is Carbon Dioxide a Non-Polar molecule?
The dipoles(polar charges) in the linear molecule cancel each other out.
What are Hydrogen Bonds?
Occur when a weak interaction between the hydrogens positive charge and the negative charge of another molecule with more electronegative atoms
What are Van Der Waals Bonds?
Weak attractions between molecules and occur between any two or more molecules and are dependent on slight fluctuations of the electron densities which are not always symmetrical around an atom
What is the order of strength of bonds?
- Covalent
- Ionic
- Hydrogen
- Van Der Waals
What are Chemical Reactions?
Occur when 2 or more atoms bond together to form molecules or when bonded atoms break apart
What are Reactants?
The substances used in the beginning of a chemical reaction
What are Products?
The substances at the end of the reaction
What are Reversible Reactions?
Those that can go either direction in which a reactant becomes a product but once a certain threshold is reached reverts back to a product
What are Irreversible Reactions?
Those that only go in one direction when the reactants become products and that is the final stage
What is the benefit of balanced questions?
Used to check the credibility of a reaction
What are Compounds?
Molecules that contain atoms of more than one type of element
