100 100 relative abundance relative abundance (%) 50 50- 10 12 mlz 06 88 94 92 For each of the two Mass Spec Graphs above: 1. Determine the average atomic mass 2. Identify the element 3. Write the symbol for each isotope 4. Indicate the number of protons, electrons, and neutrons for each isotope

1- For each of the following atoms, calculate the number of protons and neutrons in the nucleus and the number of electrons outside the nucleus (assume neutral atoms). element number of number of number of electrons mass number (A) symbol 126C protons (Z) neutrons 12 10 12 10 14 27 10 23,1Na 11 17 18 2- Calculate the atomic mass to four significant figures for carbon, given the following data: Isotope Exact Atomic Mass (amu) 12.00000 13.00335 Abundance in Nature (%) 98.89 1.110 12C 13C

Fill in the missing numbers: Symbol B+ Charge (n) 3+ #protons # neutrons # electrons Atomic Mass 210 OA Symbol B3+ Charge (n) 3+ #protons 84 # neutrons 87 #electrons 127 Atomic Mass 210 O B. Symbol B+ Charge (n) 3+ #protons 87 # neutrons 87 # electrons 90 Atomic Mass 210 OC. Symbol B3+ Charge (n) 3+ #protons 87 # neutrons 84 # electrons 127 Atomic Mass 210 O D. Symbol B3+ Charge (n) 3+ #protons 83 # neutrons 127 # electrons 80 Atomic Mass 210 OE. Symbol B3+ Charge (n) 3+ #protons 127 # neutrons # electrons 87 124 Atomic Mass 210

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Strontium (Sr, atomic number 38, average atomic mass = 87.62) naturally exists as 4 stable isotopes with masses of 84, 86, 87, and 88.  Which statement is correct?  A.Strontium-86 is the most abundant.  B.Strontium-87 is the most abundant.  C.Strontium-88 is the most abundant.  D.All strontium isotopes are equally abundant.

Which statement (s) below about isotopes of the same element is True? I. They have the same number of protons. II. They have different numbers of neutrons. iii. Isotopes are only formed by nonmetals only IV. Isotopes only differ i their number of electrons O Only IV is corrrect O only I, III are correct O Only III & IV is correct O only I, Il are correct Question 9 Lets the actual yield of a substance produced in the lab weighed 15.8 g on the scale. It was de inld ir 22 7a Calculate the % vield = (Actual/Theoretical)*100%