Matter & Chemistry Basics
What is chemistry
The study of matter and the changes it undergoes
Define hypothesis
educated guess; prediction
SI base unit for time
second
Where is the coefficient?
In scientific notation, the number that is between 1-10 and goes before the base of 10.
What is accuracy
How close a measured value is to an accepted value
What is matter
the variable that the scientist plans to change in an experiment
SI base unit for mass
kilogram
When converting a number less than 1 to scientific notation, the exponent has this sign
negative sign
According to significant figure rules, these numbers are always significant.
nonzero numbers
amount of matter in an object; stays constant
You conduct an experiment and hypothesize that salt dissolved faster in warm water than room temperature water. What is the dependent variable in the experiment?
What is a derived unit?
A unit defined by combining base units, like speed, volume, or density
A problem-solving method that uses conversion factors to change from one unit to another
dimensional analysis
Calculate percent error:
actual: 2.59 g/cm^3
measured: 1.75 g/cm^3
32.4%
What is weight
based on the gravitational force on an object
What is a control
standard used to compare in an experiment
density= mass/volume
When multiplying numbers in scientific notation, you multiply the coefficients and do this to the exponents
add them
How to calculate percent error
(actual value-measured value)/(actual value) x100
What is a model
verbal, visual or mathematical explanation of experimental data used to represent things that are hard to visualize
When you are making observations, you notice a substance is pale green, with a strong odor. What kind of data is this?
qualitative data
Convert 450 mm to meters
0.450 m
A ratio of equivalent values having different units, such as 7 palms equals 1 cubit
conversion factor
The number of significant figures in 0.00040230.
5