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misol
on FreezingBlue Flashcards.
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human body is composed of
- O C H N (majority in that order)
- P and S
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all organisms are made of
matter made of elements
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protons
- positive charge in nucleus
- distinguish atom
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neutron
no charge in neucleus
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electron
- negative charge in orbitals
- same number as protons
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isotopes
different number of neutrons same element
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radioactive neutrons
- spontaneously decay
- (help trace date, disease, trace metabolic process)
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atoms chemical properties are determined by their
electrons!
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octet rule
- •Valence shell – outermost shell
- •If an atom has more than 2 shells, the outer shell is most stable with 8 electrons
- •Atoms
- can give up, accept, or share electrons to have 8
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3 types of bonds
- hydrogen
- ionic
- covalent (polar and non polar)
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electronegativity
- stronger pull closer to itself
- ie oxygen stronger than hydrogen in H2O
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ionic bond
transfer of electrons (so one is positive one is negative) usually salt
- cat ion *lose electron positive charge
- an ion *gain electron negative charge
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covalent bond
electron is shared (even though one might have a stronger pull)
single, double, triple bonds possible
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hydrogen bond
- electronegative to one another (strong in numbers)
- easily broken
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van der waal
- positive and negative charged atoms bond
- short time because of positioning of electrons in atom
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molecule
2+ atoms with covalent bound
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polar vs non polar
- don't share evenly (cause slight charge)
- share evenly
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unique shape of bonding of atom determines
physical property
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chemical reactions
- Some chemical reactions go to completion: all reactants are converted to products
- All chemical reactions are reversible: products of the forward reaction become reactants for the reverse reaction
- Chemical equilibrium is reached when the forward and reverse reaction rates are equal
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atomic number
number of protons
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atomic mass
number of protons and neutrons
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