A+P 1.2 Basic Chemistry Flashcards
Chemistry
the science of the structure and interactions of matter
Chemical element
all matter is made up of a limited number of building blocks called chemical elements
examples of elements
H=hydrogen K=potassium
C=carbon Na=sodium
O=oxygen Fe=iron
N=nitrogen Ca=calcium
how many elements are normally present in the human body
26
Major elements of the human body
O, C, H, and N = 96%
8 lesser elements of the human body
3.6% = calcium(Ca), phosphorus(P), potasium(K), sulfur(S), sodium(Na), chlorine(Cl), magnesium(Mg), iron(Fe)
trace elements in human body
14, tiny amounts making up only .4%
Function of (I) iodine in human body
essential for thyroid to make hormones
Atoms
smallest unit of an element; consists on nucleus (protons and nutrons) and one or more electrons
Nucleus
centrally located; contains positively charged protons(p+) and uncharged (neutral) neutrons.
electrons (e-)
negatively charged particles that move about in a large space surrounding the nucleus
electron shell capacity
2 or 8
Atomic number
number of protons in the nucleus
atomic mass number
total number of protons plus neutrons
Ions
an atom that has a positive or negative charge due to unequal number of protons and electrons
Ion symbolization
chemical symbol followed by the number of its positive(+) or negative(-) charges
ex. Ca2+ = calcium with two positive charges.
Cations
Positively charged ion due to giving up electrons
Anion
negatively charged ion due to gaining electrons
Molecule
- formed when atoms SHARE electrons
- consists of 2 or more of the same or different elements
Molecular formula
indicates the number and type of atoms that make up a molecule.
Compounds
substance that contains 2 or more DIFFERENT elements
Free radical
unstable ions or molecules that can be destructive to other nearby molecules because of unpaired electrons in the outer shell. break apart body molecules by giving up unpaired electron or taking from another molecule.
*superoxide - addition of an electron to an oxygen molecule
3 general types of chemical bonds
ionic bonds, covalent bonds, hydrogen bonds
Octet rule
Biologically important atoms combine to form molecules and share electrons to form arrangements with 8 electrons in the outer shell