The Chemical Basis of Life Flashcards
What 4 elements make up 90% of the body’s composition?
Carbon
Hydrogen
Oxygen
Nitrogen
What kind of compound are these? (Inorganic or organic)
Water, phosphates, electrolytes, minerals, trace elements
Inorganic Compounds
What kind of compound are these? (Inorganic or organic)
Carbohydrates, lipids, proteins, vitamins, nucleic acids
Organic Compounds
What is an atom?
The smallest unit of matter, which are composed of three particles; Protons, neutrons, electrons
What is an element?
An element is a type of atom that is defined by its atomic number
What is an atomic number?
An atomic number is the number of protons within the atom’s nucleus
Atomic numbers distinguishes other atoms and elements
What is atomic mass?
Atomic mass of an atom is the sum of its protons and neutrons.
Electrons are not included in this calculation because they are too light (1/1836th of a proton)
What is an isotope?
Isotopes are variations of the same element, with a different number of neutrons. They are versions of elements based on the atomic mass.
ex. Carbon 14 = 8 N + 6 P
(amount of protons do not change in isotopes, only neutrons)
What is a radioisotope?
Radioisotopes are isotopes with a radioactive unstable nuclei with excess energy.
They are released as an alpha particle, beta particle, gamma radiation, or given to an electron as it decays (at different rates and intensities)
ex. How many protons and neutrons does O18 have?
Protons: 8 (always the atomic number; never changes)
Neutrons: 10
How many electrons can each electron shell hold?
Shell 1 : 2
Shell 2 : 8
Shell 3 : 8
Shell 4 : 18 (Most studied elements will only contain 3 electron shells
What is a charged atom called?
Ion
What happens to an atom that has lost an electron?
It becomes a cation
What happens to an atom that has gained an electron?
It becomes an anion
What kind of bond transfers electrons between two elements?
Ionic bonds (electrons from the outermost shell of one element are transferred to the outermost shell of the other atom)