1. Isotope Quiz Top Questions Missed

2. #1 Difficulty: Finding the number of protons  You need to know:  Atomic NUMBER is the number of P_____________________  Protons!  Atomic MASS is two things added together: P_________ & N__________  Protons and neutrons!

3. Let’s try finding the number of protons:  In a nitrogen atom with a mass number of 14 and an atomic number of 7, the number of protons is  7 (the atomic number is the number of protons)  In a sodium atom with a mass number of 23 and an atomic number of 11, the number of protons is  11 (the atomic number is the number of protons)

4. #2 Difficulty: Finding the atomic mass  You need to know:  Atomic NUMBER is the number of P_____________________  Protons!  Atomic MASS is two things added together: P_________ & N__________  Protons and neutrons!

5. Let’s try finding the atomic mass:  In a nitrogen atom with a mass number of 7 neutrons and an atomic number of 7, the atomic mass is  14 (the atomic mass is the number of protons and neutrons added together)  In a sodium atom with 12 neutrons and an atomic number of 11, the atomic mass is  23 (the atomic mass is the number of protons and neutrons added together)

6. #3 Difficulty: the particle found in all atoms  You need to know:  The periodic table has a pattern of increasing protons  Therefore, all atoms on the periodic table must have protons

7. #4 Difficulty: finding which isotope is the most abundant  You need to know:  The average atomic mass listed on the periodic table is the average mass of all the known isotopes of an element  You round the average atomic mass to the nearest whole number to find the most common isotope.  Rounding refresher:  If the number in the tenths place is less than 5, you round down (23.4 would be rounded down to 23 because 4 is less than 5)  If the number in the tenths place is 5 or more, you round up (23.5 would be rounded up to 24 because it is 5 or more)  For example, on the periodic table the average atomic mass of nickel is 58.69. The most common isotope of nickel is nickel 59.

8. Let’s find the most abundant isotopes:  Potassium has an average atomic mass of 39.30. What is the most common isotope?  Potassium-39  Chlorine has an average atomic mass of 35.34. What is the most common isotope?  Chlorine-35  Copper has an average atomic mass of 63.55. What is the most common isotope?  Copper-64

9. #5 Difficulty: Determining an electron from pictures  You need to know:  In a 0 charged atom, the number of electrons is the same as the number of protons  You can look up the name of an element using the periodic table if you know the number of protons  You need to know which parts represent the electrons in the picture An element with 4 protons is called Beryllium

10. Quiz Correction Directions: 1.Take out a piece of blank paper. 2.Write your name and period # on the top. 3.Write out 3 questions you missed. 4.Answer the 3 questions correctly. 5.Attach the quiz results to the corrections and place it in the inbox. 6.Return the quiz to Mrs. Bertoson.