CHEM 104 Harvard What Is the Difference BW Question & Hypothesis Chemistry Worksheet

Chem 104NAME_______________
Homework #3
Due Monday 14 February 2022
1. Which pairs of elements are likely to form ionic bonds (I) and which pairs are likely to
form covalent bonds (C)?
a. Carbon and hydrogen _____
b. Sodium and sulfur _____
c. Hydrogen and oxygen _____
d. Magnesium and bromine _____
2. Positively charged ions are called _______________________ and negatively charged
ions are called ______________________________
3. When the following atoms become ions what charges do they acquire?
a. Li _____
b. S _____
c. Ca _____
d. F _____
4. Write the ion symbol for the atom with the given number of protons and electrons.
a. Four protons and two electrons ______
b. 22 protons and 20 electrons _____
c. 16 protons and 18 electrons _____
d. 13 protons and 10 electrons _____
5. What element fits each description?
a. A period 2 element that forms a +2 cation _____
b. An ion from group 7A with 18 electrons ______
c. A cation from group 1A with 36 electrons _____
6. What noble gas has the same electronic configuration as each ion?
a. O2- _____
b. Mg2+ _____
c. S2- _____
d. Cl- _____
7. Write the chemical formula for an ionic compound composed of each pair of ions.
a. the sodium ion and the sulfur ion _______________________
b. the aluminum ion and the fluoride ion ___________________
c. the 3+ iron ion and the oxygen ion ______________________
d. the calcium ion and the nitrate ion ______________________
e. the magnesium ion and the carbonate ion _________________
8. The recommended dietary allowance for calcium for teenage children is 1,300 mg per
day. If a typical 8.0-fl oz glass of reduced-fat milk contains 298 mg of calcium, how
many fluid ounces of milk does a teenager need to drink to get the entire recommended
amount of calcium from this milk?