Science Test- Atoms, Protons, Ions
covalent bond
A chemical bond formed when two atoms share electrons is called a...
alloy
A mixture made of two or more elements, at least one of which is a metal is called an...
oppositely charged ions
An ionic bond is the attraction between...
polar
Because the electrons in a molecule of hydrogen flouride are more strongly pulled toward the flourine atom, the molecule is _____________.
covalent
Bonds that form between two nonmetal atoms usually are _________ bonds.
A covalent bond is a chemical bond formed when two atoms share electrons. An ionic bond is the attraction between oppositely charged ions.
Compare a covalent bond and an ionic bond.
valance electrons
Electrons involved in bonding between atoms are...
A polar bond is a covalent bond in which electrons are shared equally.
Explain what is meant by the term "polar bond."
The valance electrons within a metal are free to move.
Explain why metals are such good conductors of hear and electricity.
nonpolar
Flourine is a ________ molecule because the valance electrons are shared equally between the two fluorine atoms.
neutral
Ionic compounds are electrically...
atoms
Ionic compounds that dissolve in water conduct electricity because they break into _______ that move freely.
polyatomic ions
Ions that are made of more than one atom are examples of...
There are two bromide ions for every magnesium ion.
Magnesium bromide is an ionic compound with the chemical formula MgBr2. What does the 2 tell you?
ions
Molecular compounds that dissolve in water do not conduct electricity because no _________ are present.
electricity
Solid metals are good conductors of heat and ________.
sodium sulfide
The chemical name for the compound with the formula Na2S is...
False- Polar
True or False? A NONPOLAR bond is formed when two atoms share electrons equally.
True- Molecular
True or False? A low melting point is one property of MOLECULAR compounds.
True- Ionic
True or False? Orderly crystal shapes, high melting points, and electrical conductivity when dissolved in water are properties of IONIC compounds.
True- Structure
True or False? The properties of solid metals can be explained by the STRUCTURE of and the bonding among the metal atoms.
False- Shared
True or False? When electrons are TRANSFERRED between two atoms, a covalent bond is formed.
The alkali metals
What group contains the most reactive elements?
Two pairs of electrons shared between two atoms
What is a double bond?
They form hard, brittle crystals
What is a property of ionic compounds?
positive ion
When an atom loses an electron, it becomes a...
zero
When ions having a positive charge form bonds with ions having a negative charge, the charge on the resulting compound is _____________
Malleable
Which of the following terms means that metals can be rolled into thin sheets, as in aluminum foil, or beaten into complex shapes?
