Lab Exercises
When we were evaluating whether or not water conducted electricity, which beaker was the control: 1) Pure Water, 2) Salt & Water, 3) Bleach & Water, or 4) Sugar Water? What was the experimental variable?
Beaker 1 with pure water was the control.
The experimental variable was the addition of another substance into the water.
Practice reading the volume of a liquid in a graduated cylinder to the correct significant digits.
What is the precision of this measurement device? Which is the estimated digit?
if in the classroom, read the volume of the liquid in a graduated cylinder.
The precision will be the measurement to which the volume can be read directly from the scale.
You then estimate one more digit.
Can science be used to answer all questions?
No, science is not a giver of truth. Rather it is a process of inquiry. We formulate and test hypothesis, and over time develop theories and laws.
Explain the difference between Pure and Applied Science
Pure science gains knowledge for it's own sake. It is simply for knowledge and research purposes. Applied science solves specific problems.
The molecular formula for baking soda is NaHCO3
How many atoms does this formula represent?
How many different elements make up the compound?
6 atoms (1 of sodium, 1 of hydrogen, 1 of carbon and 3 of oxygen)
4 different elements (Na, H, C, O)
List two ways we have used in class to replicate our results
1) Repeat the experiment, 2) compare with another group's data
Read the temp of the room from the thermometer.
What is the precision of this instrument?
Which is the estimated digit?
if in the classroom, read the temperature of the room from a thermometer.
The precision will be the measurement to which the volume can be read directly from the scale.
You then estimate one more digit.
Complete a diagram showing Natural Sciences and Social Sciences as two branches under "Science".
Complete the three types of science that fall under natural science: Earth Science, Life Science and __________ Science.
What are the two branches under __________ Science?
Two branches under "Science": Natural Science and Social Science
Under Natural Science: Earth Science, Life Science and Physical Science.
Under Physical Science: Chemistry and Physics
Explain the difference between Hypothesis, Theory, and Law
Hypothesis - and educated guess
Theory - when a hypothesis has been tested and proven true multiple times, a theory may be made. Scientific laws are chosen to describe consistent patterns of phenomena in natuer.
What is the temperature at which a substance has the least possible energy and movement?
Absolute zero
Why do we average our replicated results to choose our final answer?
By averaging the results it normalizes variations in results and allows the scientist to choose are more answer more representative of the population.
Calculate the density of a 1000cm3 block of wood with a mass of 925g.
density = mass/volume
density = 925g/1000cm3
density = 0.925 g/cm3In which section of a lab report are charts and graphs often used to present observations?
Introduction, Materials and Procedure, Results, or Discussion?
Results
Which phase of matter has constant volume but not constant shape? (Solid, Liquid or Gas?)
liquid
List 6 phase changes and tell where they occur on a phase change diagram
you can reference your notes if you do not know how the diagram looks. The 6 phase changes are melting, vaporizing (or evaporating), condensation, freezing, sublimation, deposition
Describe the method of finding the volume of an object by water displacement in a graduated cylendar.
Pour some water into a graduated cylinder and read the volume. Place the object into the water so that it is completely covered by the water and measure the new volume. The volume of the object is the difference between the two volumes.
Convert 60cm to mm.
Unit multiplier:
60cm (1 m/100 cm) (1000 mm / 1 m) = 600mm
By Ladder method, you "jump" one time forward from cm to mm... so 60cm = 600 mm
Fill in the missing steps in the scientific method:
__________ -> Hypothesis -> ___________ -> Procedure -> ___________ -> Conclusion
(and looped back again to the beginning)
PURPOSE -> Hypothesis -> MATERIALS-> Procedure -> RESULTS -> Conclusion
(and looped back again to the beginning)
Explain the difference between qualitative and quantitative data.
Qualitative data describes something by it's "qualities". This is generally more subjective than Quantitative data which is obtained through measurement. Quantitative data is more objective.
Name the element for each symbol:
Na -
N -
H -
Na - Sodium
N - Nitrogen
H - Hydrogen
In the experiment with the burning candle in a pan of water,
How did we calculate the percent oxygen in the air?
We assumed that the change of the height of the water column is the same as the amount of oxygen consumed by the candle.
Therefore, we divided the height of the water by the height of the air and multiplied by 100%
Convert 2500 cm to km
Using Unit Multipliers:
2500 cm (1 m/100 cm)(1 km / 1000 m) = 0.025km
Using ladder method:
km is 4 "jumps" to the left of cm, so 2500cm = 0.025 km
Explain a "Christian World View"
world view can be described as the "lens" through which we view the world. In class we used Gen 1:1, John 3:16, and Matthew 22:37&39 to build a foundation for the Christian Worldview.
In General, Worldview answers several basic questions. These are answered below for a Christian Worldview.
Who are we? We are creatures mad in God's image
What is our fundamental problem? sin
What is the solution to that problem? Jesus
What is our primary moral duty? Love God & Neighbor
How should we live? Love the Lord and Love Others
Explain the difference between experimental groups and control groups.
A control group is used as a comparison in the experiment. It is a group that does not contain the experimental variable. Experimental groups may vary the experimental variable for the purposes of investigation.
Name the element for each symbol:
Cl -
Ca -
C -
Cu -
Cl - Chlorine
Ca - Calcium
C - Carbon
Cu - Copper