Exam 1 study guide

concave

• curves down

• read at bottom

convex

• curves up

• read at top

precision

how close the measurements in a series are to each other

accuracy

how close each measurement is to the actual value

sig figs with no decimals

• leading/trailing 0’s not significant

• 0’s between non 0’s significant

• all non 0 digits significant

sig figs with decimal

• locate 1st non 0

• first non 0 and all digits to the right are significant

sig fig add/sub rules

• decimal point is chief concern

• result will contain lowest shared decimal place

sig figs multiplication/division rules

• determine sig figs in each participant in the operation

• keep lowest number of significant digits

physical properties

characteristics of matter that can be changed without changing its composition

• characteristics that are directly observable

chemical properties

characteristics that determine how the composition of matter changes as a result of contact with other matter or the influence of energy

• characteristics that describe the behavior of matter

• only observed during a chemical reaction

metal properties

• solids

• reflective surface (high luster)

• good heat conductor

• good electric conductor

• malleable, ductile

• loses electrons easily

non metals properties

• gases, liquids, solids

• dull, non reflective surface

• heat insulator

• electric insulator

• brittle solids

• gain electrons easily

intensive (intrinsic) properties

independent of the amount of sample present

• molar mass

• density

• melting point

• boiling point

extensive (extrinsic) properties

when the amount of sample changes

• mass

• volume

homogenous mixtures

mixtures with constant compositions throughout

heterogeneous mixtures

mixtures that have compositions that are not uniform

types of energy

• motion (macro lvl)

• light (electromagnetic radiation)

• heat (micro lvl motion)

• mechanical

• sound

• chemical

• nuclear

electrons

negative charge

protons

positive charge

• found in nucleus

neutrons

neutral charge

• found in nucleus

atomic number

number of protons in an atom

atomic number of a neutral atom

number of electrons (charge balance)

mass number

sum of protons and neutrons

isotopes

same number of protons, different number of neutrons

nuclear symbols

exact contents of a nucleus (single isotope of an element)

where is mass number on a nuclear symbol located

upper left

where is atomic number of a nuclear symbol located

lower left

atomic mass

average mass of an atom of an element

cation

positive ion

anion

negative ion