University:
Miami University
Course:
CHM 141 | College Chemistry
Academic year:

2022
Views:

134

Pages:

2
Author:

Leilani Contreras

Name: ______________________________________________ Period:______ Due Date:_________ Periodic Table Homework Answers Use a periodic table to help you answer the following questions on the rows and groups in the periodic table: 1. Give the name of the element which is found in: a. Period 2, group 2 Beryllium b. Period 3 and group 15 Phosphorous c. Period 4 and group 13 Gallium d. Period 6 and group 11 Gold e. Period 4 and group 6 Chromium 2. Give the period and group number for the following elements: a. Magnesium Period 3, group 2 b. Oxygen Period 2, group 16 c. Silicon Period 3, group 16 d. Boron Period 2, group 13 e. Argon Period 3, group 18 3. How many valence electrons will atoms in group 16 of the periodic table have? 6 4. How many electron shells will elements in the 3rd period of the periodic table have? 3 5. How many valence electrons will atoms in group 2 of the periodic table typically have? 2 Name: ______________________________________________ Period:______ Due Date:_________ Periodic Table Homework Answers 6. Compare the number of valence electrons of atoms which are metal elements to those which are non-metals, in the first 20 elements. The number of valence electrons is indicated by the group which the element is located in. For the first 20 elements, groups 1 and 2 (metals) have 1 and 2 valence electrons respectively. For groups 13 to 18 (both metals and non-metals), these will have between 3 and 8 electrons depending on the group. For metals such as aluminium, they will have less than four valence electrons, in Aluminium’s case this is three. Non-metals such as nitrogen will have 4 of more valence electrons, so for nitrogen, this is five. 7. Describe the relationship between the number of valence electrons in the elements of the periodic table and the groups and periods in the table. Atoms which are found in the same group have the same number of valence electrons. For example Beryllium, Magnesium and Calcium are in group 2 and will therefore have 2 valence electrons. With each successive period, another energy level is added. For instance, in the group one metals, Lithium has 2 energy levels, while sodium has three energy levels. As we move across the periodic table from the left to the right, the number of electrons in each group increases by 1. For example Sodium has 11 electrons in total, magnesium has 12 electrons etc.