Chem 14BL week 1-4 Flashcards
What is accuracy?
the closeness of a result to the true value
What is precision
the closeness of a set of results to each other; reproducibility of a result; number of significant figures in a result
What are significant figures?
any nonzero digit from 1-9; zeros between nonzero digits; ending zeros after a nonzero number with a decimal point
In addition or subtraction, how many number of decimal places in the answer ?
the smallest number of decimal places in the data
In multiplication or division, the number of significant figures in the answer
the smallest number of significant figures in the data
When taking the log of a number, how many number of decimal places in the answer?
the number of significant figures of the number in the log
When taking the antilog of a number, how many number of significant figures in the answer?
the number of decimal places of the exponent in the antilog
Standard deviation formula?
the square root of the sum of the difference between each entry and the mean squared all over the number of entries
Average deviation formula?
the sum of the absolute value of the difference of each individual number and the mean all over the number of entries
Percent relative average deviation?
the average deviation divided by the mean multiplied by 100
Absolute error?
expresses the margin of uncertainty associated with the measurement; represented by delta; has units
Relative error?
also known as percent error, inherent error, or precision; compares the size of the absolute uncertainty with the size of its associated measurement; represented by absolute error divided by the measured quantity; no units
Addition or subtraction of absolute error?
change of C equals change of A plus change of B
Multiplication or division of absolute error?
change of C equals parantheses change of A divided by A plus change of B divided by B end parantheses multiplied by C
Addition or subtraction of relative error?
change of C over C equals change of A divided by C plus change of B divided by C
Multiplication or division of relative error?
change of C over C equals change of A divided by A plus change of B divided by B