Scientific Method Metrics

English Metric Do Now: Make a list of some units you know. Try and classify them as metric or the English system.

PrefixSymbolMeaningNumerical Value Giga-G10 9 1,000,000,000 Mega-M10 6 1,000,000 Kilo-k10 3 1,000 Hecto-h Dekada BASEg, l, m Deci-d Centi-c Milli-m Micro-m Nano-n

Base Units MeasurementBase Unit Length Mass Volume Temperature Time

Measuring always involves some estimation Certain Digits: A digit that represents a mark on a scale or a non-blinking number on a display. Uncertain Digits: A digit that represents the space between the marks on a scale or a blinking number on a display what is certain? what is uncertain?

Tools for Measuring

The Kelvin Temperature Scale Absolute Zero: The point at which all motion of particles stops (no more kinetic energy) Can we ever reach absolute zero?

Convert between the following temperatures: oC oCK 0 o C 450 K - 40 o C 225 K K = o C + 273

Properties of Water oFoF oCoCK What is the freezing point of water? What is the boiling point of water?

Chemistry: the study of: the composition, structure, and properties of matter and the changes it undergoes

Scientific Method Logical approach to solving problems 1. Observation 2. Problem 3. Hypothesis 4. Experiment - Data - Analysis 5. Conclusion

What is a Hypothesis? an educated guess

Observations Qualitative: quality, non-numeric terms Quantitative: quantity, numerical description weatherheightweightspeed

FEATURE FILMS ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCES OF YEARS.

System: specific portion of the experiment that has been selected for study In an experiment… Constant: experimental conditions that do not change Control: experimental condition that is used as a standard for comparison Variable: experimental condition that does change

Complete Example problem on Notesheet

Scientific Notation 602,200,000,000,000,000,000, x x Some numbers are very large or very small, so a short hand notation is needed! Too large: Too small:

N x 10 n N is a number between 1 and 10 n is a positive or negative integer if n is a negative number, the full number is a small decimal if n is a positive number, the full number is a large number 3.69 x ________________ x 10 5 ________________ General Notation:

What is Density Density: ratio of mass to volume  “how much stuff is packed into a given area” Density of Liquids: Density gradients are made by layering substances of varying densities Greater density is on the __________ Lower density is on the __________

Water: Density = 1.0 g/mL Objects > sink Objects < float Solids have a greater density than liquids. Solid: Liquid: So, when water freezes… ice sinks. Right?

WATER IS A SPECIAL CASE!!! The density of ice is less than water! This allows fish to survive at the bottom of the lake in winter!

D = m V m D V

Example 1 A sample of aluminum metal has a mass of 8.4 g. The volume of the sample is 3.1 cm 3. Calculate the density of aluminum. Given:Unknown: Solution: Answer: m D V

Example 2 A piece of iron has a density of 5.8 g/mL. It displaces a volume of 23.6 mL. What is the mass of the piece of iron? Given:Unknown: Solution: Answer: m D V