Calculate the mass percent composition of calcium in Ca(NO3)2.
A) 24.4%
B) 39.2%
C) 11.6%
D) 16.2%
E) 59.6%
A) 24.4%
What type of reaction is responsible when a free element is converted to a compound?
A) Oxidation-reduction
A compound with molar mass of approximately 80 g/mol has the
following composition (mass percent): C: 75.9%, H: 6.4%, and N: 17.7%.
What is its molecular formula?
C) C5H5N
Which two compounds have the same empirical formula?
E) C2H5OH and C6H18O3
In the reaction: 2Fe(s) + 3Cl2(g) ->2FeCl3(s) (same as question 8), if 43 grams of iron were reacted, how many grams of FeCl3 could be produced?
C) 125
Which compound has a molar mass closest to 100 g/mol?
A) C7H10
Which is a valid, general definition of a salt?
A) The compound besides water that is formed in an acid-base reaction.
How
many moles of water may be formed when 12 moles of hydrogen gas are
mixed with 11 moles of oxygen gas and are allowed to react? 2H2 + O2 --> 2H2O
C) 12
Which of the following reactions could be classified as a double-displacement reaction?
C) Pb(NO3)2 (aq) + H2S (aq) --? 2HNO3 (aq) + PbS (s) (OK)
In one word, why do we use average atomic masses for the elements?
C) isotopes
In the reaction: 2Fe(s) + 3Cl2(g) ->2 FeCl3(s), if 43 grams of iron were reacted, how many moles of iron were reacted?
D) 0.77
.
If
magnesium were to react with the non-metal fluorine, how many electrons
would each Mg atom lose, and how many would each F atom gain?
B) Mg: 2; F: 1
What is the net charge of a precipitate formed by two aqueous solutions?
D) Neutral, because an insoluble salt compound is formed.
Consider the generic reaction A + B —? C. This is an example of a
B) synthesis.
Calculate the molar mass of lead(II) nitrate (in g/mol).