Chemistry Unit 1
All other measurements with
exception of luminous intensity, quantity of a substance(mole), temperature, and electric current are defined in terms of time, length, and mass **extra side note-volume is defined in terms of length
Time
-According to Sir Isaac Newton, time is that which flows onward uniformly -SI unit for Time is second usually abbreviated with an s. -is a fundamental, indefinable, unit in Science/ not a derived quantity -does not depend on the measurement of another quantity
Derived Units
-Are those that are calculated, that is, arrived at through multiplying or dividing some combination of the seven base units, what we call 'fundamental units' -Example: Molar Mass Is expressed in moles per gram (mol/g) This derived unit is one unit(mol) divided by another unit g
Kilo-
-Symbol K -Exponent 10^3 -decimal 1,000 -Fraction of a Base Unit 1,000xbase
Mega-
-Symbol M -Exponent 10^6 -Decimal 1,000,000 -fraction of Base Unit 1,000,000xbase
Deci-
-Symbol d -Exponent 10^-1 -decimal 0.1 -Fraction of a Base Unit 1/10 of base
3 instruments commonly used to measure metric volumr in a chinstrap lab are
-graduated cylinders -pipettes -burettes
Length
-is the measurement describing the distance from one point to another -SI unit is the meter; abbreviation:m -is a fundamental, indefinable unit of science / not a derived quantity I think hold up
Mass
-is the third fundamental unit in chemistry -is the quantity of matter a body possesses -SI unit of mass is the kilogram ***extra side note: 1kg is approximately the same as 2.2 pounds at sea level, but remember here that pounds are a unit of force, not mass
2 factors to consider in making a measurement:
-measurement's accuracy -precision
Centi-
-symbol c -exponent 10^-2 -decimal 0.01 -Fraction of a Base Unit 1/100 of abase
Deka-
-symbol dk -exponent 10 -decimal 10 -Fraction of the Base Unit 10x base
Hecto-
-symbol h -Exponent 10^2 -decimal 100 -Fraction of a Base Unit 100x base
Milli-
-symbol m -exponent 10^-3 -decimal 0.001 -Fraction of a Base Unit 1/1000 of base
Nano-
-symbol n -exponent 10-9 -decimal 0.00000001 Fraction of a Base Unit 1/1,000,000,000 of base
Micro-
-symbol um -exponent 10^-6 -decimal 0.000001 -Fraction of a Base Unit 1/1,000,000 of base
Precision
The degree of exactness of a measurement; described by the number of significant digits used to express value
Accuracy
The degree to which a measurement approaches a standard or true value
Electric current
Ampere(A)
Length
The measure of the distance from one point to another
SI system
The metric system of units
Mass
The quantity of matter a body processes
Luminous intensity
Candela(cd)
Base unit is the unit under ?
Consideration such as the meter, liter, or second
Temperature
Kelvin(k)
Mass
Kilogram(kg)
Length
Meter (m)
Base unit
Meter, second, liter
Quantity of a substance
Mole(mol)
Time
Second(s)
Time
That which flows onward uniformly
