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

Chemistry Practice Problems: Atomic Mass Calculations II

[Miss part one? Check out Atomic Mass Calculations I.] [Download the accompanying PDF worksheet.] 1. Magnesium has three naturally occurring isotopes, 24Mg (78.99%, 23.9850 amu), 25Mg (10.00%, 24.9858 amu), and 26Mg.  Determine the percent abundance and isotopic mass of 26Mg. … Read More



Chemistry Practice Problems: Atomic Mass Calculations I

[Download the accompanying PDF worksheet.] Calculate the Average Atomic Mass Calculate the average atomic mass of an element with two naturally occurring isotopes: 85X (72.15%, 84.9118 amu) and 87X (27.85%, 86.9092 amu).  What is this element? Chromium has the following … Read More



Chemistry Practice Problems: Heat & Specific Heat Capacity (Introductory)

[View the accompanying Lesson on Heat & Specific Heat Capacity here.] [Download the accompanying PDF worksheet here.] Perform the following calculations, being sure to give the answer with the correct number of significant digits. A car with magnesium wheels is parked … Read More



Chemistry Practice Problems: Compound Unit Conversions

[View the accompanying Lesson on Compound Unit Conversions here.] [Download the accompanying PDF worksheet here.] Perform the following calculations, being sure to give the answer with the correct number of significant digits. A certain medication is set to deliver through an … 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 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