Show:
Valence Electrons
Ionic Bonds
Covalent Bonds
Misc.
100
electrons involved in bonding between atoms are
valence electrons
100
Ionic compounds that dissolve in water conduct electricity because they break into _________ that move freely
ions
100
ionic compounds form hard, brittle ______________
crystals
100
which group contains the most stable elements?
noble gases
200
when an atom loses an electron, it becomes a
positive ion
200
In the ionic compound, magnesium bromide, MgBr2, what does the 2 stand for?
2 bromine ions for every magnesium ion
200
What is one property of molecular compounds?
Low melting point; low boiling point
200
metals form this type of bond with nonmetals
ionic bond
300
atoms tend to form bonds so that they have ___ valence electrons and become more stable.
8
300
In a chemical formula for an ionic compound, which item is written first?
the positive ion
300
how many electrons are shared in a double bond?
2 pairs or 4 electrons
300
Is Carbon Dioxide a polar or nonpolar molecule?
nonpolar. Because of its linear construction, the oxygen atoms pull in opposite directions in equal strength and cancel out, so the molecule is nonpolar.
400
Draw an electron dot diagram for Beryllium (Be). How many dots should be drawn around the element's symbol? Explain
2: elements in group 2 have 2 valence electrons.
400
how many elements of group 1 would be needed to react with group 16
2
400
Describe a nonpolar bond? Give 1 example.
A covalent bond when 2 atoms share electrons equally, like H2 gas.
400
Describe properties that would help you to distinguish an ionic compound from a molecular compound.
Ionic compounds have high melting points and high boiling points compared to molecular compounds. Ionic compounds that are dissolved in water or melted will conduct electricity. Molecular compounds do not conduct electricity in either case.
500
How do Valence Electrons relate to the chemical reactions of an element?
Valence electrons are the electrons that are most loosely held by the atom and the ones that are involved in chemical reactions. Chemical reactions occur whenever valence electrons are shared or transferred between atoms. The number of valence electrons determines how these reactions take place and what kind of bonds atoms can form.
500
Write a balanced chemical formula and name the compound formed between Potassium (K) and Oxygen (O)
K2O (K should have 2 as a subscript) Potassium Oxide
500
Draw an electron dot diagram for water. What special properties does this structure provide?
H20...see pg 140 in textbook. This is a polar molecule, van der Waals forces attract water molecules to one another causing surface tension, cohesion...water to balloon up on a penny, allow a gecko to grip smooth surfaces (glass)
500
Compare a covalent bond and an ionic bond.
A covalent bond is formed when two atoms share valence electrons. Neither atom loses electrons or takes electrons from the other. No charged particles form. In an ionic bond, one or more electrons are transferred from one atom to another. Atoms that lose electrons become positively charged ions, and atoms that gain electrons become negatively charged ions. These oppositely charged particles then attract each other.