chemistry chapter 8
In an equation, the symbol for a substance in water solution is followed by
(aq)
Which coefficients correctly balance the formula equation CaO + H2O → Ca(OH)2?
1,1,1
Which coefficients correctly balance the formula equationNH4NO2(s)→ N2(g) + H2O(l)?
1,1,2
When the equation Fe3O4 + Al → Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?
9
which of the following is a formula equation for the formation of carbon dioxide from carbon and oxygen?
C +O2 = CO2
in writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is
H2
Magnesium bromide (aq) + chlorine (g) yields
MgCl2(aq) and Br2(l)
in the word equation, sodium oxide + water → sodium hydroxide, the formula for
NaOH
What is the balanced equation for the combustion of sulfur?
S(s) + O2 (g) = SO2 (g)
what is the small whole number that appears in front of a formula in a chemical equation?
a coefficient
when a solid produced by a chemical reaction separates from the solution it is called
a precipitate
The ability of an element to react is the element's
activity
What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions?
activity series
according to the law of conservation of mass, the total mass of the reacting substances is
always equal to the total mass of products
An element in the activity series can replace any element
below it on the list
Predict what happens when calcium metal is added to a solution of magnesium chloride.
calcium chloride forms
The reaction of calcium oxide, CaO, with water yields
calcium hydroxide
When heated, a metal carbonate decomposes into a metal oxide and
carbon dioxide
which observation does not indicate that a chemical reaction has occurred?
change in total mass of substances
to balance a chemical equation, it may be necessary to adjust the
coefficients
The equation AX → A + X is the general equation for a
decomposition reaction
The reaction represented by the equation 2HgO(s) → 2Hg(l) + O2(g) is a(n)
decomposition reaction
In what kind of reaction does a single compound produce two or more simpler substances?
decompostition reaction
In what kind of reaction does one element replace a similar element in a compound?
displacement reaction
In what kind of reaction do the ions of two compounds exchange places in aqueous solution to form two new compounds?
double-displacement reaction
The equation AX + BY → AY + BX is the general equation for a
double-displacement reaction
The reaction represented by the equation Pb(NO3)2(aq) + 2KI(aq) → PbI2(s) + 2KNO3(aq) is a
double-displacement reaction
The decomposition of a substance by an electric current is called
electrolysis
Active metals react with certain acids, such as hydrochloric acid, to yield a metal compound and
hydrogen
Group 1 metals react with water to produce metal hydroxides and
hydrogen
When potassium reacts with water, one product formed is
hydrogen gas
Predict what happens when lead is added to nitric acid.
hydrogen is released
Oxides of active metals, such as CaO, react with water to produce
metal hydroxides
Some metals, such as iron, react with steam to produce hydrogen gas and a
metal oxide
Predict what happens when zinc is added to water.
no reaction occurs
The equation A + BX → AX + B is the general equation for a
single-displacement reaction
The reaction represented by the equation Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq) is a
single-displacement reaction
In what kind of reaction do two or more substances combine to form a new compound?
synthesis reaction
The equation A + X → AX is the general equation for a(n)
synthesis reaction
The reaction represented by the equation 2Mg(s) + O2(g) → 2MgO(s) is a
synthesis reaction
in a chemical reaction
the mass of the reactants equals the mass of the products
What can be predicted by using an activity series?
whether a certain chemical reaction will occur
