Dr. Kent McCorkle, or "Dr. Kent' to his student, has helped thousands of students be successful in chemistry.

Chemistry Practice Problems: Scientific Notation

[View the accompanying Lesson on Scientific Notation here.] [Download the accompanying PDF worksheet.] Convert the following numbers into scientific notation: 1.  192 Gs 2.  0.00478 fm 3.  50800 qt 4.  390.0200 K 5.  0.08200 µm 6.  4000 °F   Convert the following … Read More



Chemistry Lesson: Scientific Notation

[View the accompanying Scientific Notation Practice Problems here.] What is Scientific Notation? Scientific notation is a method of writing really large or really small numbers in a more concise form that removes all of the extraneous zeroes.  For example, 0.0000000072 … Read More



Chemistry Lesson: Significant Digits & Measurements

[View the accompanying Significant Digits & Measurements Practice Problems here.] Why Significant Digits? Significant digits (also called significant figures or “sig figs” for short) indicate the precision of a measurement.  A number with more significant digits is more precise.  For example, … Read More



Chemistry Practice Problems: Significant Digits & Calculations

[View the accompanying Lesson on Significant Digits & Calculations here.] [Download the accompanying PDF worksheet here.] Perform the following calculations, being sure to give the answer with the correct number of significant digits. 8.010  ×  41.907 993.4  ÷  6.022 76.0  –  38.119 … Read More



Chemistry Lesson: Significant Digits & Calculations

[View the accompanying Significant Digits & Calculations Practice Problems here.] Determining the Correct Number of Significant Digits After performing a calculation, we often obtain more digits than are warranted by the measurements that produced it.  In order to determine the correct … Read More



Chemistry Lesson: Significant Digits & Rounding

[View the accompanying Lesson on Significant Digits & Measurements here.] Significant Digits & Rounding All numbers from a measurement are significant.  However, we often generate nonsignificant digits when performing calculations. We get rid of nonsignificant digits by rounding off numbers. There are three … Read More



Chemistry Practice Problems: Significant Digits & Measurements

[View the accompanying Lesson on Significant Digits & Measurements here.] [Download the accompanying PDF worksheet here.] How many significant digits does each of the following numbers have ? 42,784 cm 120 mi 9842.010 kg 0.0819 sec 0.000200500 ft 4300. lb 8.600°C 0.553092 … Read More