All About Valence Electrons
Which term describes when a metal can be made into different shapes and rolled into thin sheets?
Malleability
If one atom in a molecular compound has a stronger pull on the electrons, then the molecule will become....
polar
Solid metals are good conductors of what?
Heat and Electricity
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.
What happens when an atom loses an electron?
It becomes a positive ion
What are the properties of ionic compounds?
High boiling points, high melting points, ability to conduct electricity when melted or in liquid state, form hard crystals
If two atoms in a molecule share three pairs of electrons, what kind of bond is it?
A Triple Bond
What is a metal solid?
Explain how a bond forms between sodium and chlorine in sodium chloride (NaCl).
Sodium has one valence electron and chlorine has seven valence electrons. The lone valence electron from sodium is lost and is transferred to the chlorine atom. The result is a sodium ion with a charge of 1+ and a chloride ion with a charge of 1–. The oppositely charged ions attract each other and the charges balance to make a compound that is electrically neutral.
Which group has the most reactive elements: family 1, family 2, family 16 or family 18
Family 1 because it has 1 valance electron
What is the chemical name for NaS
Sodium Sulfide
What is it called when two atoms share two pairs of electrons?
A double bond
What happens to the valence electrons when a metal and metal form a compound?
The valence electrons are in a "sea" freely moving
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.
What happens when a polar and nonpolar elements mix?
They do not mix
When writing the name or formula for an ionic compound, which item is written first--the name of the positive ion, or the name of the negative ion?
The name of the positive ion
What properties do molecular compounds share?
Must have at least 2 of these: low melting point, low boiling point, does not conduct electricity
What is a mixture made of two or more elements, in which at least one is a metal?
Alloy
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.
Family 18 has how many valence electrons?
8--except for Helium, it only has 2 (must have full answer for credit!)
Ionic compounds that dissolve in water conduct electricity because they break into what?
free moving ions
Why don't molecular compounds that dissolve in water conduct electricity?
there are no ions (charged particles) present
The properties of solid metals can be explained by the ______________ of and the ________________ among the metal atoms.
structure - bonding
Explain why metals are such good conductors of heat and electricity.
A metal crystal consists of positively charged metal ions embedded in a “sea” of loosely held valence electrons that can move around easily. Heat travels through materials as the increased motion of the particles in the hotter parts of the material is passed along to the particles in the cooler parts. In a metal, since particles are easily set in motion, heat is easily transferred, or conducted. The same is true for the conduction of electricity. Electricity can flow when charged particles, such as electrons, are free to move. Since the electrons in a metal crystal can move freely among the atoms, electricity is easily conducted.