SCIENCE & CHEMISTRY
Science...
a) asks questions like "why?" and "how?"
b) literally means "knowledge"
c) is a systematic approach to problem solving
d) all are true of science
d - all are true of science
Convert 5 grams (g) to milligrams (mg)
5,000 mg
1,400,000,000 m
1.4x109 m
Are leading zeros ever significant?
ex: 0.000 3
No!
LIST QUESTION! 100 PTS FOR EACH CORRECT!
What are the 7 "fundamental measurements?"
Length, mass, time, temperature, amount, electric current, luminous intensity
Define "chemistry" without using the word "chemical(s)" in your answer.
Chemistry is the study of ___ and ___.
matter and change
substances and changes
Convert 3 deciliters (dL) to Dekaliters (DL)
0.03 DL
Put the size of a hydrogen atom (cm) into standard notation
1x10-8 cm
0.000 000 01 cm
ex: 50,005 m
Yes!
The 2nd step of the scientific method is to make your most educated guess to attempt to answer your scientific question. This "guess" is called a/an __.
hypothesis
The first step of the scientific method is to...
a) observe things in nature
b) define or identify a problem
c) ask a question
d) all are true of the first step in science
d - all are true of the first step in science
Convert 5 Terabytes (TB) to Megabytes (MB)
5x106 MB
or
5,000,000 MB
Multiply:
2x104 x 4x102
8x106
or
8,000,000
When are trailing zeros significant?
Only when a decimal is present!
A group of students measure and calculate gold's density three times, and the results are as follows:
15.2 g/mL, 15.1 g/mL, and 15.3 g/mL
Gold's actual density is 19.3 g/mL.
Were the groups measurements accurate? Precise?
They were precise, but not accurate
This type of data collected during an experiment does NOT involve numbers.
Qualitative
Convert 7 m3 to mm3
7x109 mm
or
7,000,000,000 mm
5x109 / 1x105
5x104
or
50,000
How many significant figures?
0.000 300 300 g
0.000 300 300 g
(6 - everything from the first 3 to the right)
Give 2 examples of "derived" measurements.
(there are LOTS to choose from)
examples: speed (distance/time), area (length x width), volume (l x w x h), density, (mass/volume), force (mass x velocity)
What is the only letter in the alphabet that does not appear on the Periodic table?
J
Water's density is 1.0 g/cm3
What is water's density in kg/m3 ?
1,000 kg/m3
The volume of a sphere = 4/3(3.14)r3. A dust grain is approximated as a sphere with a radius of 2 x 10⁻⁶ meters. If the density of the silicon dioxide it's made of is 3300 kg/m³, find the mass of one dust grain.
1.1 x 10⁻¹³ kg
Round your answer with correct sig figs:
3.173 g + 1.1 g
4.3 g
*When adding and subtracting, round to the lesser of the decimal places in the numbers you're adding or subtracting
Multiply and round to correct sig figs:
3.3 cm x 1.50 cm
5.0 cm2
*when multiplying or dividing, the answer must be rounded to the same number of sig figs as the lesser or least of the numbers you are multiplying or dividing