Medical Chemistry - Chapter 2 A

One type of Atom. The simplest type of matter with unique physical and chemical properties. Properties (color, density, combustibility) are unique for each element.

Matters whose composition is fixed.

elements, compounds, mixtures

populations of atoms. However, several exist naturally as molecules

an independent structure consisting of 2 or more atoms that are chemically bound together.

two atom molecules (ex. Oxygen)

type of matter composed of two or more different elements that are chemically bound together. (their atoms have actually joined chemically)

1) fixed composition (because of fixed composition, elements are also considered a substance).
2) its properties are different from those of its component elements.
3)Unlike an element, a compound can be broken down into simpler substances - its component elements.

a group of 2 or more substances that are physically intermingled (physically mixed). Unlike a compound, the components of a mixture can vary in parts by mass. Since composition isn't fixed, its not a substance.

One type of Atom. The simplest type of matter with unique physical and chemical properties. Properties (color, density, combustibility) are unique for each element.

Matters whose composition is fixed.

elements, compounds, mixtures

populations of atoms. However, several exist naturally as molecules

an independent structure consisting of 2 or more atoms that are chemically bound together.

two atom molecules (ex. Oxygen)

type of matter composed of two or more different elements that are chemically bound together. (their atoms have actually joined chemically)

1) fixed composition (because of fixed composition, elements are also considered a substance).
2) its properties are different from those of its component elements.
3)Unlike an element, a compound can be broken down into simpler substances - its component elements.

a group of 2 or more substances that are physically intermingled (physically mixed). Unlike a compound, the components of a mixture can vary in parts by mass. Since composition isn't fixed, its not a substance.

A mixture retains many properties of its components.

1) Law of mass conservation
2) Law of definite (or constant) composition
3) Law of multiple proportions

the total mass of a substance does not change during a chemical reaction (the number of substances may change and their properties must, but total mass stays same).

no matter what its sources, a particular compound is composed of the same elements in the same parts (fractions) by mass.

the part of the compounds mass that each element contributes.

if elements A and B react to form two compounds, the different masses of B that combine with a fixed mass of A can be expressed as a ratio of small whole numbers.

Atomic number - the number of protons

Mass number - total number or protons and neutrons in the nucleus of an atom.

are the atoms of an element that have different numbers of neutrons and therefore different mass numbers.
All isotopes of an element have nearly identical chemical behavior.

carbon-12 atom

1/12 the mass of a carbon-12 atom

1) Law of mass conservation
2) Law of definite (or constant) composition
3) Law of multiple proportions

the total mass of a substance does not change during a chemical reaction (the number of substances may change and their properties must, but total mass stays same).

no matter what its sources, a particular compound is composed of the same elements in the same parts (fractions) by mass.

the part of the compounds mass that each element contributes.

if elements A and B react to form two compounds, the different masses of B that combine with a fixed mass of A can be expressed as a ratio of small whole numbers.

Atomic number - the number of protons

Mass number - total number or protons and neutrons in the nucleus of an atom.

are the atoms of an element that have different numbers of neutrons and therefore different mass numbers.
All isotopes of an element have nearly identical chemical behavior.

carbon-12 atom

1/12 the mass of a carbon-12 atom

a method for measuring the relative masses and abundances of atomic-scale particles very closely.

the weighted average of the masses of its naturally occurring isotopes.

the mass of the isotope relative to the mass of the standard carbon-12 isotope.

horizontal rows. Do not have similar chemical properties.

vertical columns. Have similar chemical properties.