Semester 1 Final Flashcards
(105 cards)
What is the chemical formula for ozone?
O3
What does the ozone layer do?
Protects living things on Earth from ultra violet waves
What are the two types of ozone?
Air-naturally occurs in the upper atmosphere (good)
Ground- created by exhaust and aerosol (large amounts are toxic)
How is ozone being depleted?
Chlorofluorocarbons (CFCs) and nitrous oxide
Independent variable
Value scientists plan on changing
Dependent variable
Value that changes in response to the change in the independent variable
Constant
Values that must stay the same throughout the experiment
Control
Standard used for comparison
Qualitative data
Information describing color, odor, shape, or some other physical characteristic (not able to be measured)
Quantitative data
Numerical information describe how much, little, big, tall, or fast (measurable Ex: height, length, volume)
Theory
Explanation of natural phenomenon based on many observations and investigations over time
Scientific law
Relationship in nature supported by many experiments
Difference between a theory and a law
There are no exceptions to laws; theories can be proved wrong
How do you calculate significant figures when multiplying/dividing?
Number of the least significant figures of the numbers being multiplied/divided= number of significant figures in answer
Ex:124.0 x 2.4= 297.6= 300
How do calculate significant figures when adding/subtracting?
Where the shortest number ends= where significant figure of product ends
Ex: 35.01 + 72.3+ 61= 168.31= 168
How to determine significant figures when measuring
Sig figs go to the closest measuring mark, then a guess
Ex: measuring cm: 55.40
Chemical change
Change that involves one or more substances changing into new substances
Ex: burning, reaction, neutralization
Physical change
Change that alters a sample without changing its composition
Ex: tearing, grinding, mixing
Accuracy
How close a measured value is to the accepted value (right answer)
Precision
How close a series of measurements are to eachother rather than the accepted value (May be wrong, but consistently wrong)
Density
Amount of mass per unit of volume
D= m/v
Label for density?
G/cm cubed or g/mL
(1cm cubed= 1 mL
Slope formula?
x2-x1
Between what numbers must the coefficient be in scientific notation?
1 and 10