CHEM 24112 Chapter Notes - Chapter 4: Lead

Look at the schematic diagram for carbon. What do all three carbon atoms (and ions) have in common? What do all four hydrogen atoms (and ions) have in common? What do all magnesium atoms (and ions)have in common? Look at a periodic table (for example, in your text). Considering your answer to CTQs 1-3, what is the significance of the atomic number, above each element in the table? How many protons are in all chlorine atoms? Do you think chlorine atoms exist with 18 protons? Why or Why not? Confer with your team and once you agree, write your answer in a complete sentence. How many electrons are found in 12C? 13C? 13C? Engage in a team discussion to identify what feature distinguishes a neutral atom from an ion. Write the consensus answer in a complete sentence. Engage in a team discussion and once your team agrees, write a formula for calculating the charge of an ion. Spokesperson (Presenter): be prepared to share the team answer with the class. A positively charged ion is called a cation (pronounced "cat ion"), and a negatively charged ion is called an anion (pronounced "an ion"). Which term applies to the magnesium ion? Process Analyst (Reflector): comment to your team on strengths and needed improvements for your teamwork so far.

A certain isotope X contains 23 protons and 28 neutrons. Determine the mass number of this isotope and identify the element. Which element, isotope, or ion listed below contains 35 protons, 46 neutrons, and 36 electrons? 7. 8. 81Kr+ b. 81Br c. 81Kr d. 81Br- 9. and horizontal rows are vertical columns found on a periodic table are called called 10. How many of the following is/are true about the element fluorine? Fluorine is a halogen Fluorine is in period 2 of the periodic table. Fluorine is a nonmetal Fluorine is in Group 7A IV 11. An ion with a 3+ charge contains 23 electrons. Which ion is it? a. Fe3* 12. True or False Two isotopes of the same element differ only in the number of protons found in b. V3* c. Ca3+ d. Sc3+ the nucleus 13. Which of the following pairs are isotopes? A) Ca+2 and Mg+2 B) 199Hg and 200Hg C) 180 and 19F D) 238U and 238Np 14. In nature, "Valentinium" consists of two isotopes, Valentinium-69 (Mass 68.926 with natural abundance of 60.1%) and Valentini um-71 (Mass = 70.925 with natural abundance of 39.9%). Calculate the relative atomic mass of the element "Valentinium". (2 points)