Measurements Flashcards
Week 2
tool of science
Math
We measure mass quantity of
matter
Measurement
invariable and independent
Mass (kg,g)
- Varies relation to distance
- Depend on the gravitational force
- The lower the gravitational force, the lower the weight and vice versa
Weight
- Space occupied by substance or object
- Bigger space = bigger volume
Volume (liter, mL)
- Distance covered of the certain object
- How long or short the object is
Length
Volume, mass degrees Fahrenheit, Celsius (American system), or kelvin (absolute temperature). Amount of kinetic energy present in a substance.
Temperature
High Temp (hot)
Large K.E
Low Temp (cold)
Low K.E
Water Boils at
100 degrees celsius, 112 degrees Fahrenheit, 373 Kelvin
- Derived dimension and derived units.
- lightness /heaviness of a substance
- Dense or not dense
- Depends on mass per given volume
Density (g/mL)
The ratio of density of the substance being referred to and density of water.
Specific Gravity
- Close to each other
- e.g. 76,77,76
Precise
Close agreement in true value
Accurate
(Internet, books)
True values
Measurement can be
Metric System (Philippines)
Metric System
Kilogram (mass)
- Rounded off
- Reliability in terms of large numbers
- More accurate = more significant
Significant Figures
- useful for very large and very small numbers, especially in non-SI units.
- Diamond is a pure carbon
Arrangement of carbon
Scientific Notation
empirical science
Chemistry
Chemistry is studied by
- Measuring physical properties and observing chemical reactions. (Boiling point, formation of bubbles? change in color so there is a reaction)
- Supported by facts and evidences
are created to explain observations and organize collected data.
Models
recorded via measurements. (Recorded the
temperature)
Observation in Science
included in observation
UNIT OF MEASUREMENTS
- how close the observed value is to the “true” value.
Accuracy
- the spread in values obtained from measurements; the reproducibility of values.
- Trial 4 close to the trial 1,2,,3
- As long as magkalapit ‘yong values REGARDLESS if tama
- how close a set of measurements
are to each other
Precision
- may make a measurement randomly too high or too low. (e.g., variation associated with equipment limitations)
- There can be random errors like there is a problem in equipment.
- Maling calibration = maling results
Random Error
- may make a measurement consistently too high or too low. (e.g., the presence of an impurity)
- More on the procedures
- Contamination = impurity
Systematic Error
fps system (foot – pound – second)
English System or British System
cgs system (centimeter-gram – second) mks system (meter – kilogram – second) - SI (Systeme Internationale)
Metric System
Chemists quantify data
expressing collected data with units and significant figures.
- designate the type of quantity measured.
- Units of mass are pound, grams, kilogram
- Lengths are meters, millimeters
Units
- provide scale to a base unit.
- Centi - 100
- Milli - 1000
Prefixes
- The base unit designates the type of quantity being measured.
- meter
Base Units
cm, dm
smallest Scale
km
Bigger Scale
indicate the amount of information that is reliable when discussing a measurement.
Significant Figure
are the base units of science.
SI units (from French Système International)
Some units comprise combinations of these base units
derived units
