Chapter 2
Draw a solution map to convert a measurement in ounces to grams (1lb=16oz)
...
Express each number in scientific notation 37,692,000-1,360,000-19,306,000-568,000
...
How many sig. figs. are there in exact #s? What kinds of #s are exact?
...
What are the rules for rounding numbers?
...
What is the difference between mass and weight?
...
Write conversion factors for each miles to kilometers-kilometers to miles-gallons to liters-liters to gallons
0.6214mi/1km 1gal/3.785
...
32
Express each number in scientific notation 0.00000000007461m-0.00000158mi-0.000000632m-0.000015m
7.461x10tothe-11-1.58x10tothe-5-6.32x10tothenegative7-1.5x10tothenegative5
What is the conversion factor?
A conversion factor is a quantity used to relate two-seperate units. They are constructed from any two quantities known to be equivalent.
What limits the number of sig figs in a calculation involving only multiplication and division?
For calculations involving only multiplication and division, the result carries the same number of sig figs as the factor with the fewest sig figs.
How do we determine sig figs in calculations involving both addition/subtraction and multiplication/division?
In calculations involving both, do the steps in parenthesis first, nect determine the correct # of sig fig in the intemediate answer, then do remaining steps.
What limits the # of sig figs in a calculation of only addition and subtraction
Incalculations only using
Why is scientific notation useful?
Often scientists work with a very large or very small number that contain a lot of zeros. Scientific notation allows these numbers to be written more compactly, and the information is more organized.
What are the basic SI units of length, mass and time?
The basic SI unit of length is the meter. The kilogram is the SI unit for mass. Lastly, the second is the SI unit for time.
What is density? Explain why density can work as a conversion factor. Between what quantities does it convert?
The density of a substance is the ratio of its mass to its volume. Density is a fundamental property of materils and differs from one substance to another. Density can be used to relate two seperate units, thus working as a conversion factor. Density is a conversion factor between mass and volume.
Explain why units are important in calculations?
Units act as a guide in the calculation and are able to show if the calculation is off track. The units must be followed in the calculation, so that the answer is correctly written and understood.
Why is it necessary to include units when reporting scientific measurements
Without units, the results are unclear and it is hard to keep track of what each seperate measurement entails.