Definitions
Cohesion
The force of attraction between molecules of the same substance so that they tend to stay together
Bromine is a Group 7A element. What is the charge on a bromide ion?
1-
What do subscripts tell us in a chemical formula?
How many atoms of an element
Propane is a gas we use for BBQ pits, which is composed of 3 carbons and 8 hydrogens. what is the chemical formula for propane?
C3H8
If an element gains an electron in an ionic bond, it becomes a _______?
anion
Polar molecule
A molecule that has slight positive and negative charges due to an imbalance in the way electrons are shared
Which pair have the same electron configuration?
Na+ and Kr
Na- and Kr-
Na and Kr
Na+ and Kr+
Na+ and Kr
Na must lose an electron to have a stable elcetron configuration. Kr already has one since it is a noble gas
What do Coefficients tell us in a chemical equation?
How many molecules of an atom or compound is needed to balance a chemical equation.
Ethanol (C2H5OH) is used as a gas additive. How many atoms are in one molecule of ethanol?
9
H. What does the dot represent?
1 valence elctron that hydrogen has.
Covalent bond
A chemical bond in which two atoms share one or more pairs of valence electrons
Water is a polar molecule. What two types of molecules will dissolve in water?
Polar molecules and ions.
Which type of bonding in elements allows for malleability?
Metallic bonds
Ammonia is a common household cleaning agent, which is composed of 1 nitrogen, and 3 hydrogens. Write the chemical formuls for ammonia.
NH3
In a chemical equation, what are the elements or compounds on the right called?
products
Adhesion
The force of attraction between molecules of different substances so that they tend to stick together
Sulfur is a Group6A element. What is the charge on a sulfide ion?
2-
Balance this equation
Fe + Cl2 = FeCl3
2Fe + 3Cl2 = 2FeCl3
Iron Sulfate {Fe2(SO4)3} is used to treat iron deficiency anemia. how many atoms does one molecule of iron sulfate have?
17
If an element loses an electron in an ionic bond, it becomes a _________?
Cation
Ionic bond
A chemical bond formed between oppositely charged ions
Describe the charges on a water molecule.
It is a polar molecule. The hydrogen has a slight positive charge and the oxygen has a slight negative charge
How do atoms achieve stable electron configurations?
by either transferring electrons (ionic bonds) or sharing electrons (covalent bonds)
Balance this equation
S8 + O2 --> SO3
S8 + 12 O2----> 8 SO3
Describe hydrogen bonding
Formed between molecules not atoms. Hydrogen has a slightly positive charge while oxygen has a slightly negative charge in water. Thus, it attracts other water molecules and they bind together tightly using a hydrogen bond