T or F
The SI base unit for the amount of particles in a substance is the liter.
False - mole
How many SF does this number have: 0.01500060
7 SF
What is a fraction equal to 1 called which contains both the original unit and its equivalent value in a new unit?
conversion factor
Which is not a step in problem solving:
estimating, calculating, calibrating, checking
calibrating
Significant digits only apply to which type of data
Measured data, not counted/pure numbers
When working equations, the answer cannot contain more significant digits than the measurement given with the least number of significant digits.
True
Accurately subdivided into measurement units
graduated
Write on the board the equation for density.
Ms. Rogers will verify
What helps indicate the precision of an instrument to data
significant digits
Any device made for the purpose of refining, extending, or substituting for the human senses when measuring is called
an instrument
It is best to round off at intermediate steps for compound calculations.
false - don't round until the very end
Change 157 dm to ____ km.
0.0157 km
Write on the board the correct equation for percent error:
Ms. Rogers will verify
The actual measurement is 7.89 g
Your measurements are 10.37 g, 8.65 g, 10.97 g.
Low or high accuracy? Low or high precision?
What are the 2 essential parts of a measurement
Number and unit
The first step in problem solving is to determine how to solve the problem.
False - read the problem first
Two part: Give the correct power of 10 for both of these prefixes:
A. d
B. c
a. 10^-1
b. 10^-2
Calculate the percent error: You measure the mass in a reaction to be 8.67 g. Theoretical calculations predict a mass of 10.5 g.
17.4 %
The actual measurement is 7.89 g
Your measurements are 7.88 g, 7.91 g, 7.87 g.
Low or high accuracy? Low or high precision?
High accuracy and high precision.
Units of measurement that come from basic SI units
derived units
If a scientist is extremely careful and using high precision instruments, a perfect measurement is possible.
False - perfection is impossible, especially with human error / tech error / etc.
Two part: Give the correct meaning for both of these numbers: (ex. hundredth --> centi-)
A. thousandth
B. tenth
a. milli-
b. deci-
Calculate this problem: Find volume in mL of a 585 g copper wire with a density of 7.963 g/mL. Use correct number of SF in your answer.
73.5 mL
The actual measurement is 7.89 g
Your measurements are 3.53 g, 3.57 g, 3.54 g.
Low or high accuracy? Low or high precision?
High precision, low accuracy.
Give 3 of the 7 SI base units and what they represent
meter (length) mole (particles)
kg (mass) ampere (current)
second (time) candela (light)
kelvin (temp)