Chemistry 142 Review - Chemistry 142 Review Chapter 1: -...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chemistry 142 Review Chapter 1: - Science: an approach to gather knowledge about the physical universe based upon the scientific method. - Scientific method: the systematic process system used in pursuing scientific investigation. - Steps that are involved in pursuing an investigation by means of the scientific method: o Idea: topic of investigation developed by asking the appropriate questions o Hypothesis: tentative explanation or prediction concerning some phenomenon o Experiment: testing of the hypothesis involving controlled procedures. o Scientific data: the results obtained (from experiments) after careful measurements and observations o Formulation of a general rule: summary of the scientific data obtained after observing a particular pattern or trend o Law: consistent testing of the general rule over extended period of time. o Theory: successful arrival of the law leads to postulation of the theory. - Base Units: mass, length, amount of a substance, time temperature, current, and luminous intensity: - Common Prefixes: o Gaga – 10^9 o Mega – 10^6 o Kilo – 10^3 o Deci – 10^-1 o Centi – 10^-2 o Milli – 10^-3 o Micro – 10^-6 o Nano – 10^-9 o Pico – 10^-12 - The degree of uncertainty is dependent upon the calibration of the instrument that is employed for making the measurement. - The uncertain digit will always be one digit more than the number of digits for which an instrument is calibrated. - “the number of certain digits” + “the number of uncertain digits” = the number of sig figs. - All numbers that can be counted are considered to be exact numbers. - All numbers that are involved in defined relationships are considered to be exact and hence they are not significant.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
- All non-zero numbers are considered to be significant while zeros may either be significant or non significant depending upon their position in the measurement. o Leading zeros are non-significant o Captive zeros are significant o Trailing zeros are only significant if a decimal is involved. - Accuracy: the agreement of a particular value with a true value - Precision: degree or amount of agreement among several measurements of the same quantity. - For the numerical operations of multiplication and division the number of significant figures in the answer will be determined by the numeral or measurement that is the least accurate. - for addition and subtractions, the number of significant figures in the answer will be determined by the numeral or measurement that is the least precise. - Chemistry: the systematic study of the structure, composition, and properties of matter and changes that accompany it. - Atoms: the smallest particle of matter that retains its characteristic property. -
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 13

Chemistry 142 Review - Chemistry 142 Review Chapter 1: -...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online