Chemistry Chapter 1 Flashcards
(36 cards)
What is chemistry?
The study of matter and how it changes.
-matter, change
What is matter?
Matter is anything that has mass and takes up space.
-mass, space
What is a unit?
A unit is a quantity that describes the measurement being made.
-measurement, quantity
Which is more important: the unit of measurement or the number?
BOTH!! The unit of a measurement is just as important as the number. You must always list the unit!
Which is longer: an object that is 1 inch long or an object that is 1 centimeter long?
The 1 inch object.
What does the term significant figure mean? What are the three rules for determining significant figures?
A significant figure is a digit in a measurement that contributes to the measurement’s precision.
Does not always mean mathematically important:
A) All non-zero figures are significant. (1 2 3 4 5 6 7 8 9)
B) A zero is significant if it is between two significant figures. (1.304508)
C) A zero is also significant if it is at the end of a number and to the right of the decimal point. (18.00)
How many significant figures are in 102.0 inches?
4
How many significant figures are in 0.0405 cm?
3
How many significant figures are in 12,000 inches?
2
Describe the difference between precision and accuracy.
Precision is determined by the instrument you are using to make your measurement. If you have a very fine measuring instrument, you can report your measurement with a lot of decimal places (increase number of decimal places = increase in precision). Accuracy indicates how correct your measurement is. You can use a very precise measurement, but use it wrongly and will end of with an answer that is precise but not accurate,
-determined by instrument vs how correct
When completing a measurement, where can you always expect to find some sort of error?
You can always expect to find some error in the last significant figure.
What is unit conversion?
Unit conversion is the knowing the relationship between different units and being able to switch between the units.
What is the Conversion Relationship?
The conversion relationship tells you the relationship between two different units.
-unit, relationship
How many inches are in 20.12 cm? (Note: the conversation relationship is 2.54 cm = 1 in).
7.921 inches
What is a base unit?
Used in the metric system, it is the unit by which all other units defined by.
-unit, defined, metric
Complete the abbreviations and meanings for the following metric prefixes:
mega
Kilo
Hecto
Deca
Centi
Milli
Micro
Nano
Mega = M = 1,000,000
Kilo = k = 1,000
Hecto = H = 100
Deca = Da = 10
Centi = c = 0.01
Milli = m = 0.001
Micro = u = 0.0000001
Nano = n = 0.000000001
Provide the prefixes and meanings for the following abbreviations.
M
k
H
Da
c
m
u
n
M = mega = 1,000,000
k = kilo = 1,000
H = hecto = 100
Deca = Da = 10
c = Centi = 0.01
m = Milli = 0.001
u = micro = 0.0000001
n = nano = 0.000000001
If an Olympic pool is 0.05km in length, how long is that in meters?
50 m
Kilo = 1,000
0.05 km / 1 X 1,000 m / 1 km = 50 m
The diameter of a dime is 17.9 mm. How many meters is that?
0.0179m
What is scientific notation and what problem can it solve in science and when are you required to use it?
Scientific notation is used when a number is either too small or too large to be conveniently written in decimal form.
Using scientific notation allows you to maintain the number of significant figures in the measurement. (E.g. 5000 has 1 significant figure, but 5.00 x 10 to the third has 3 significant figures).
Use scientific notation when significant figures can only be properly expressed with scientific notation.
-too large/small #
-proper scientific notation
What is area and how do you calculate it?
Area is the squared distance unit of a measurement.
A = l x w
What are derived units?
Derived units are units that are achieved through doing math. Example: squared meters when completing an area calculation.
-math
What is volume and what is the formula to calculate volume?
Volume is the measure of how much space something takes up.
Volume = l x w x h
-measurement, space, units cubed
What is a graduated cylinder?
A graduated cylinder is cylinder in which liquids can be poured. There are markings on the side (graduations) that allow for reading the volume of the liquid in the cylinder.
