Flashcards for Chapter 2 in Chemistry

What is a base unit?
a defined unit in a system of measurement that is based on an object or event in the physical world and is independent of other units
What is density?
the amount of mass per unit volume
What is the equation for density?
What is a derived unit?
a unit defined by a combination of base units
What is a conversion factor?
a ratio of equivalent values used to express the same quantity, always equals 1 and changes the units of a quantity without changing its value
What is dimensional analysis?
a systematic approach to problem solving that uses conversion factors to move from one unit to another
What is an error?
the difference between an experimental value and an accepted value
What is a graph?
a visual display of data
What is kelvin(K)?
the SI base unit of temperature-not measured in degrees
What is the SI base unit for mass?
What is the metric unit of volume equal to one cubic decimeter?
What is the SI base unit for length?
What is percent error?
the ratio of an error to an accepted value
What is the SI base unit for time?
What is scientific notation?
a method used to express any number as a number between 1 and 10 multiplied by 10 raised to a power(exponent) an example would be 1.24 x 1012
What is a significant figure?
the number of all known digits reported in measurements plus one estimated digit
What is the equation for percent error?
How do you convert Celsius to Kelvin?
K=273+temperature in Celsius
How do you find Slope?
you divide the dependent y variable by the independent x variable-rise over run
What is the difference between accuracy and precision?
Accuracy refers to how close a measured value is to an accepted value where precision is how close a series of measurements are to one another.
When multiplying scientific notations what do you do?
multiply the coefficients and add the exponents
What do you do in the division of numbers in scientific notation?
divide coefficients and subtract the exponents
How many significant digits does 12.3 have? Give the rule explaining why.
3; Non-Zero numbers are always significant
How many significant digits does 1098.3 have? Give the rule why.
5; because Zeros between nonzero numbers are always significant
How many significant digits does 12.0 have? Give the rule why.
3 because All final zeros to the right of the decimal are significant
How many significant digits does 0.0023 have? give the rule why.
2; In a decimal number, zeros that come before the significant number are not significant
How many significant digits does 23,000 have? Give the rule why.
2; trailing zeros without a decimal are not significant, however if the number was 23,000.0 the zeros would be significant
What determines the number of significant digits when adding, subtracting, multiplying, or dividing?
the number with the lowest number of significant digits
How do you round 5’s when there are zeros after them or no digits after?
Round down if the digit before the 5 is even and round up if the digit before the 5 is odd
What are the 3 major types of graphs?
Circle graph, Line Graph, and Bar Graph
What graph is useful for showing parts of a whole?
circle graph
What graph is useful in showing how quantities vary across categories?
Bar graph
What graph is used to show the relationship between the independent variable and the dependent variable?
Line graph
What is interpolation when interpreting a graph?
it is any data points that are included on the line between the recorded points of data
What is extrapolation?
extending a line beyond the plotted points in order to estimate futher data
What is the base unit for (a)temperature, (b)length, (c) mass, (d)time?
a. Kelvin(K); b.meters(m); c. kilogram(kg); and d.seconds(s)