Midterm Exam Flashcards
What is 3,456 km expressed in scientific notation?
3.456 x 10³ km
How many significant figures are there in the measurement 0.000000345
three, don’t count leading zeros
What is the quantity 34.5 milligrams expressed in grams?
0.0345 g (move decimal 3 to left)
What is the purpose of using significant figures in the science lab?
to determine the precision of measurement
What is the easiest instrument to use to measure volume?
graduated cylinder
What is the quantity 340 meters expressed in kilometers?
0.34 km
What are important safety rules to follow when working with open flames?
Do not leave lighted burner unattended, tie back hair, avoid wearing loose clothing
Perform the following calculation to the correct number of significant figures. 2.00 cm x 0.0040 cm =
.0080 cm² (give answer in 2 sig figs, because least precise number had 2 sig figs)
What is an important safety rule to follow when working with an acid?
wear safety goggles
If an acid is spilled on your skin, you should tell the teacher and ___.
rinse thoroughly with water
Known mass is 4.40 g. Data was 2.20,2.21,2.20,2.21,2.20. The data reflects -
Low accuracy and high precision.
What type of change is tearing a piece of paper?
Physical change
What type of change is rusting?
Chemical change
What type of mixture is soil?
heterogeneous
What type of mixture is Kool-Aid?
homogeneous
What type of mixture is salt water?
homogeneous
What type of mixture is Gatorade?
homogeneous
What type of mixture is tossed salad?
heterogenous
What type of change is explosion?
chemical
What type of change is corrosion?
chemical
What type of change is food spoilage?
chemical
What type of change is boiling?
physical
What type of change is sublimation (solid to gas)?
physical
What type of change is dissolving in water?
physical
What type of mixture is raisin bread?
heterogenous
What type of mixture is sand and water?
heterogenous
What are some evidences that a chemical change has occurred?
Change in color, production of a gas, change in smell, change in temperature, a solid forms (precipitate)
When a change in state,(like liquid to gas or solid to liquid), occurs, is this evidence of a chemical change?
no
What mass of sodium chloride would be produced if 10 grams of sodium reacted completely with 20 grams of chlorine?
10 + 20 = 30 grams, due to Law of Conservation of Mass
What is each vertical column of the elements in the periodic table called?
group
What is each horizontal column of the elements in the periodic table called?
period
What state of matter has a definite volume and takes the shape of its container?
liquid
What state of matter has a definite volume and shape?
solid
What state of matter has no definite volume and no definite shape?
gas
What is the term describing the process of a gas changing to a solid?
deposition