University:
Carleton College
Course:
CHEM 122 | Introduction to Chemistry
Academic year:

2022
Views:

141

Pages:

2
Author:

larbiwxcvbn

The Chemical Basis of Life Exercise 3 (Modules 2.4-2.6) These modules introduce atoms. It is most important to know what the subatomic particles are, where they are located in an atom, and that atoms of different elements differ because they contain different numbers of protons. Some atoms not covered in these modules are compared below. You can figure out the subatomic particles they contain based on the con cepts in the modules. First, fill in the blanks. Then sketch each atom, labeling and coloring protons red, neutrons gray, and electrons blue. (Coloring will help you focus on and re member which is which.) Symbol Atomic Number C 6 2. Nitrogen-14 /J 7 3. Chlorine-35 QI 35 4. Oxygen-16 Q_ /6 5. Oxygen-17 Il 17 Element 1. Carbon-12 �:� . Mass }/umber Number of Protons Number of Neutrons Number of Electrons 12 6 6 6 J-· 14 17 17 8 Chapter 2 Exercise 4 . (Modules 2.6-2.8) , Atoms of four elements important to life are diagrammed below. Pay particular attention to their electron shells. Remember that atoms with incomplete outer electron shells partic ipate in chemical reactions that allow them to attain complete outer shells: 2 electrons for a hydrogen atom, 8 electrons for most other elements important to life. NITROGEN (N) Atomic number = 7 CHLOHINE (Cl) Atomic number = 17 HYDROGEN (H) Atomic number = 1 CALCIUM (Ca) Atomic number = 20 1. Given the information and diagrams above, show how electrons would be trans ferred between calcium and chlorine atoms to form calcium and chloride ions, which would then attract each other to form calcium chloride, CaC12 . (Hint: An atom can gain or lose more than one electron.) Ca +t 2. Using the information and diagrams above, show how nitrogen could form covalent bonds with several hydrogen atoms, forming a molecule of ammonia. What would be the molecular formula for ammonia?