Scientific Method and Writing a formal lab report in Science

A. Scientific Method- Steps

1) Question or Problem2) Research/Background info3) Hypothesis4) Experiment/Procedure5) Results6) Analysis/Conclusion7) Sources of error/future studies

B. Writing a Formal Lab ReportAll lab write-ups should follow this

format. It should look familiar!

-Size 12 font-1.5 spacing-Do NOT use the words “I”, “We”, “Our”,

etc..-Hand your reports in on time! I will

check rough drafts for you, but they must be shown to me at least a day before the due date.

II. Metrics- SI International SystemA. Measuring Lengtha) Metrics are the only

measurement units used in this class.

b) 1 meter = 100 cmc) milli=one thousandthd) Kilo= one thousande) 1 km= 1,000 mf) Down Right Easy- when

decreasing, move down the stairs and the decimal to the right. Increasing, move up stairs and decimals to the left

g) Converting metrics to EnglishEX: miles to kilometers

EX: Down Right Easy

Kids Have Dropped Over Dead Converting Metrics

*All measurements MUST have TWO numbers after the decimal.

Metrics Practice1. A potato has the mass of 0.25kg. Your recipe

for potato salad calls for 1 kilogram of potatoes. How many potatoes do you need?

2. 800mg= kg3. 25.73m= cm4. 1.00 ml of water is poured into a cube. What is

the volume of the cube?5. 0.95L= ml6. 1,685.36dg= dkg7. 0.03972hm= mm

4 potatoes

0.0008

2,573

16.8536

3,972

950

1.00 cm3

Mass- the amount of matter in an object

Q: What is the difference between mass and weight?

Mass is the amount of atoms in an object while weight is the force of gravity on an object

Q: What are units for mass?grams

Q: If I am 3000kg on Earth and the moon has 1/6 the gravity of Earth, what is my mass on the moon? Mass= 3000kg still- matter does not change

Q: If I weigh 125lbs on Earth, what would I weigh on the moon?

Weight on moon= 21lbs

a)Mass depends on what is making up the object.b)A dense material such as lead is made up of many tightly packed atomic particles and is more dense.

EX: An anvil in space maybe weightless but not massless! EX: One gram is approximately one small paper clipQ: What instrument measures mass?

Triple Beam Balance

Volume- the amount of space an object takes up.EX: One liter is approximately a medium

size carton of milk

a) Measured with a graduated cylinder or if cubic, Length x width x height

b) Units: a) Liquid = mLb) Solid = cm^3

c) True or false, an object with a large mass has a large volume.

d) Measure liquid at the bottom of the meniscus-always

Q: How is a graduated cylinder accurately read?

from the bottom of the meniscus at eye level

Density

A. Density- mass per unit of volume1. Formula- Density =

mass/volume2. Units= g/mL or g/cm3

3. Density is determined by the alignment of the atom, closely packed= more dense

• How can the density of a fluid change if it never changes chemically?

Density Analysis Questions…Q: How does density control the motion of a submarine?

To dive, water is taken into tanks, increasing density so its weight is greater than the buoyant force. The tanks are filled until the density is equal to the water to allow it to float level. Water is then released to cause the sub to rise at an angle to the surface.

Q: Why does a helium balloon float?Helium is less dense than air, which is 78% N and 21% O

Q: Jupiter has a diameter that is larger than ten Earth’s, how is it possible for earth to be more dense than the planet Jupiter?Jupiter is made of gas, Earth is made of dense rock and metal

Q: Explain, in terms of density, why did the Titanic sink?Before the hole, Titanic was a steel balloon full of air After the hole was formed, water replaced the air on the ship causing the density to increase and the ship to sink.

Q: Some canoes have compartments on either end for storage and airtight to protect from objects getting wet. Explain how it is impossible for these canoes to sink.The compartments are water tight, therefore, water will never fill the compartments, they will remain full of air-and always be less dense than the water.

Temperature

We use…..Degrees Farenheit.-Freezing point of water = 32°F-Boiling point of water = 212°F

Metric system uses…..Degrees Celsius.-Freezing point of water = 0°C-Boiling point of water = 100°C

CONVERSION

IF YOU START WITH °F... IF YOU START WITH °C…

C = (F - 32)/1.8 F = (C x 1.8) + 32

***Examples on board***

Dimensional Analysis:

• An easy process to help you convert metric to English units.

• Remember to always setup your units first, then, fill in the appropriate numbers.

• Remember that units will “cancel each other out”. For example, 6/6 = 1, cm/cm = 1

• Let’s practice on the board!

Scientific Notation

• The scientific notation is the proper way to write extremely large or extremely small numbers while STILL keeping two numbers after the decimal.

• It allows for a “short-cut” in science for writing these large numbers but still actually demonstrating the size of the number.

• Let’s practice on the board!