CHEM 1127Q Chapter Notes - Chapter 1-2: Graduated Cylinder, Significant Figures, Atomic Number

• School: UConn
• Department: Chemistry
• Course: CHEM 1127Q
• Professor: Joseph De Pasquale

Document Summary

Exact number - number derived by counting or by definition. Read at the bottom of the meniscus in the graduated cylinder. Uncertainty - estimate of amount by which measurements differs from the true value. Addition/subtraction of numbers - add/subtract then round to the same number of decimal places. Multiplication/division of numbers - multiply/divide then round to same number of significant figures. Round so that the digit is an even number. Accuracy - a measurement is considered accurate if it yields a result that is very close to the accepted value, accurate values agree with a true value. Precision - measurements are said to be precise if they yield very similar results when repeated in the same manner. Dimensional analysis - the units of quantities must be subjected to the same mathematical operations as their associated numbers. Unit conversion factor - ratio of two equivalent quantities expressed with different measurement units. T f = 9/5 t c + 32.