Unit 02 - Data Analysis

sig figs conversion factors and stuff

mass; volume; density; temperature

Basic properties of matter

SI system

International system of units scientists use

Base units

Units used to measure but are independent values of measurement

Second (s)

Base unit to measure time

Meter (m)

Base unit to measure distance / length

Kilogram (kg)

Base unit to measure mass

Kelvin (K)

Base unit to measure temperature

Mole (mol)

Base unit to measure amount of substance, a count of particles to manage big numbers

Liters (L)

Unit to measure volume

Degrees Celsius (C)

Derived unit to measure temperature

kg/m³

Derived unit to measure density

Derived unit

ALL other units that are NOT base units

derived; Kelvin

Celsius is a _____ unit of _____.

K=C+273K

Equation to find temperature

Density=mass/volume

Equation to find density

Conversion factor

Factor that is used to change between units; it gives a relationship between them two

Metrix prefixes

Prefixes for units used to adjust the size of the unit

Mega (M); 1000000; one million

Prefix used for 10^6

Myriad (my); 10000; one ten-thousand

Prefix used for 10^4

Kilo (k); 1000; one-thousand

Prefix used for 10³

Hecto (h); 100; one-hundred

Prefix for 10²

Deca (da); 10; one-ten

Prefix for 10^1

Deci (d); 0.1; one-tenth

Prefix for 10^-1

Centi (c); 0.01; one-hundredth

Prefix for 10^-2

Milli (m); 0.001; one-thousandth

Prefix for 10-³

Micro (mc); 0.000001; one-millionth

Prefix for 10^-6

Nano (n); 0.000000001; one-billionth

Prefix for 10^-9

Accuracy

A measure of how close your measured value is to the actual value

Precision

A measure of how reproducible a bunch of repeated measurements are

Closeness

Accuracy = _____

Consistency

Precision = _____

Average=number of values/sum of all values​

Equation to find an average

average

Measurements that are not accurate and not precise can have an _____ that is accurate.

Measurement error

The difference between a following quantity and its true value

Percent=error in measurement value/actual value of thing measured

Equation to find a measurement error

Significant figures

Used to refer to the digits of a measurement

Significant figures

The digits that matter in a measurement or calculation

Accuracy

The _____ of a measurement or calculation is reflected by the number of significant figures we include

nonzero; zeroes between nonzeros; zeros after a nonzero number with a decimal

Rules of identifying significant figures

placeholder zeroes; zeroes at the beginning of a number with a decimal; zeroes at the end

Rules of identifying insignificant figures

addition or subtraction; decimal places

When _____ is performed, the answer is rounded to the number with the least _____.

multiplication or division

When _____ is performed, the answer is rounded to the number of digits that corresponds to the least amount of significant figures

confidently explain their data, make informed decisions, and communicate findings effectively.

Why would a scientist want their measurements to be both accurate and precise?