Chemistry Exam Tests
the number 14.809 rounded to three significant figures is
14.8
convert 8.64 kg. to pounds ( 1 lb. = 453.6 g.)
19.0 lb.
which group on the periodic table shows where the alkali metals are located?
1A
a student finds that the weight of an empty beaker is 12.024g. she places a solid in the beaker to give a combined mass of 12.108g. to how many significant figures is the mass of the solid known?
2 significant figures
the number 2.00152 rounded to four significant figures is
2.002
find volume of an object w/a density of 3.14 g/mL and a mass of 64.0 g.
20.4 mL
if a 100. g. sample of platinum metal has a volume of 4.669 mL, what is the density of platinum in g/cm^3
21.4 g/cm^3
calculate molar mass, in g/mol, of Fe2(CO3)3 {subscripts; 2,3,3}
291.73 g/mol
which group on the periodic table shows where the alkaline earth metals are located?
2A
silver nitrate reacts in solution with potassium chromate to yield a silver chromate precipitate and soluble potassium nitrate. write balanced equation
2AgNO3 + 2KCrO2 ---> Ag2CrO2 + 2KNO3 (subscripts: O3,O2, Ag2, O2, O3)
aqueous sodium hydroxide reacts with carbon dioxide gas to yield soluble sodium carbonate and liquid water. Write balanced equation
2NaOH(aq) + CO2(g) ----> Na2CO3 + H2O(l) [subscripts; O2, Na2, O3, H2]
how many significant figures are in the number 1.89 • 10^3
3 figures
determine the molar mass of KAl(SO4)2 x 3H2O
312.28 g/mol
convert 683.7 K =__________ ºC
410.7 ºC
an atom of the isotope 137^Ba consists of how many protons (p), neutrons (n), and electrons (e) ?
56 p, 81 n, 56 e
use the rules of significant figures to calculate the following: 6,167 + 70 =
76
which group on the periodic table shows where the halogen elements are located?
7B
express 8,349 in scientific notation
8.349 x 10^3
which group on the periodic table show where the noble gases are located?
8B
convert 33.6 ºC = _________ ºF
92.5 ºF
aqueous barium nitrate reacts with sulfuric acid [H2SO4(aq)(subscript 2, 4)] to yield a barium sulfate precipitate and nitric acid [HNO3(aq)(subscript 3)]. write a balanced equation
Ba(NO3)2 + H2SO4(aq) ----> BaSO4 + 2HNO3(aq) (subscript 3, 2, 2, 4, 4, 3)
what is the formula for dibromine heptoxide?
Br2O7
an organic thiol compound is 38.66% C, 9.73% H, and 51.61% S by mass. What is the empirical formulas?
C2H6S
a compound with an empirical formula of C2H3Br2 has a molar mass of 373.69 g/mol. what is the molecular formula?
C4H6Br4
what is an empirical formula for C10H22B2 [subscripts; 10, 22, 2]
C5H11B [subscripts; 5,11 ]
an unknown compound with a molar mass of 223.94 g/mol consists of 32.18% C, 4.50% H, and 63.32% Cl. find the molecular formula for the compound.
C6H10Cl4 [subscripts; 6, 10, 4]
solid calcium carbonate reacts with hydrochloric acid [HCl(aq)] to yield aqueous calcium chloride, carbon dioxide gas, and liquid water. write a balanced equation
CaCO3(s) + 2HCl(aq) ----> CaCl2(aq) + CO2(g) + H2O(l) [subscripts; O3,Cl2, O2, H2]
determine the formula of the hydrate that contains 20.3% Cu, 8.95% Si, 36.3% F, and 34.5% H2O
CuSiF • 6H2O
solid ferric oxide reacts with solid aluminum metal to yield solid aluminum oxide and solid iron metal. write a balanced equation
Fe2O3(s) + 2Al(s) ----> Al2O3 + 2Fe(s) [subscripts; Fe2, O3, Al2, O3]
write chloric acid, and chlorous acid
HClO3 (aq), and HClO2 (aq)
name this binary compound; Fe2O3
Iron(III) Oxide
magnesium nitrate reacts in solution with potassium hydroxide to yield a magnesium hydroxide precipitate and soluble potassium nitrate. Write a balanced equation
Mg(NO3)2 + 2KOH ---> Mg(OH)2 + 2KNO3 [subscripts; O3, )2, )2, O3]
write the formula for ammonia
NH3
aqueous sodium chloride reacts with aqueous lead(II) chloride precipitate and aqueous sodium nitrate. write balanced equation
NaCl (aq) + PbNO3 (aq) ----> PbCl + NaNO3 (aq) (subscripts 3)
aqueous lead(IV) nitrate reacts with aqueous sodium sulfate to yield a lead(IV) sulfate precipitate and soluble sodium nitrate. Write a balanced equation
Pb(NO3)4(aq) + Na2SO4(aq) ---> Pb(SO4)2 + NaNO3 [subscripts; O3, )4, Na2, O4, O4, )2]
solid zinc metal with sulfuric acid to yield aqueous zinc sulfate and hydrogen gas. Write a balanced equation
Zn(s) + H2SO4 (aq) ---> ZnSO4 + 2H [subscripts; H2, O4, ]
aqueous zinc chloride reacts with dihydrogen monosulfide gas to yield a zinc sulfide precipitate and hydrochloric acid. write a balanced equation
ZnCl2(aq) + H2S(g) ----> ZnS + 2HCl(aq) [subscripts; Cl2, H2]
which of the following is an ion? a.) B3+ b.) NaCl c.) He d.) 14^C e.) none
a.) B3+
an anion is defined as a.) a charged atom or group of atoms with a net negative charge b.) a stable atom c.) a group of stable atoms d.) an atom or group of atoms with a net positive charge
a.) a charged atom or group of atoms with a net negative charge
the name for NH4NO3 is a.) ammonium nitrate b,) ammonium nitrogen trioxide c.) ammonia nitrogen oxide d.) hydrogen nitrogen oxide e.) hydrogen nitrate
a.) ammonium nitrate
which one of the following elements is most likely to form a 2+ ion a.) calcium b.) carbon c.) fluorine d.)oxygen e.) sodium
a.) calcium
Rutherford's experiment with alpha particle scattering by gold foil established that... a.) protons are not evenly distributed throughout an atom b.) electrons have a negative charge c.) electrons have a positive charge d.) atoms are made of protons, neutrons, and electrons e.) protons are 1840 times heavier than electrons
a.) protons are not evenly distributed throughout an atom
a solution can be distinguished from a compound by its a.) variable composition b.) liquid state c.) heterogeneous mixture d.) lack of color
a.) variable composition
ion
atom or group of atoms that has a net positive or negative charge
which are the following are isotopes? a.) 14^C and 13^C b.) 14^C and 14^N c.) 14^N and 14^N^3- d.) 12^C and 12^CO e.) 14^N and 14^N2
b.) 14^C and 14^N
which of the following is an example of an empirical formula a.) C9H12 b.) C9H18S2 c.)C6H6 d.)N2O4 e.)C2H2O2
b.) C9H18S2 [subscripts; 9, 18, 2]
what is the formula for the ionic compound containing calcium ions and nitrate ions a.) Ca3N2 b.) Ca(NO3)2 c.) Ca2NO3 d.) Ca2NO2 e.)CaNO3
b.) Ca(NO3)2
what are the two different ions present in the compound NH4NO3 a.) NH4-, NO3+ b.) NH4+, NO3- c.) N^3-, H+, O2- d.) NH4^3+, NO^4- e.)NH4+, NO^3-
b.) NH4+, NO3-
which of the following involves NO chemical change? a.)burning paper b.)boiling water c.)baking a cake d.)lighting a match e.)driving a car
b.) boiling water
which of the following elements is chemically similar to magnesium? a.) sulfur b.) calcium c.) iron d.) nickel e.) potassium
b.) calcium
what type of compound is IF5 a.) ionic b.) molecular c.) acid d.) base e.) hydrate
b.) molecular
density is an example of a... a.) chemical property b.) physical property c.) qualitative property d.) chemical change e.) physical change
b.) physical property
name the acid H2SO3 (dissolved in water), a.) Sulfuric acid b.) sulfurous acid c.) hydrosulfuric acid d.) persulfuric acid e.) hyposulfurous acid
b.) sulfurous acid
what are the seven elements that naturally occur as diatomic molecules
bromine, oxygen, fluorine, iodine, nitrogen, chlorine, hydrogen
magnesium ion, Mg^2+, has a.) 12 protons and 13 electrons b.) 24 protons and 26 electrons c.) 12 protons and 10 electrons d.) 24 protons and 22 electrons e.) 12 protons and 14 electrons
c.) 12 protons and 10 electrons
what type of compound is HBrO2 a.) ionic b.) Binary c.) acid d.) base e.) hydrate
c.) acid
which of these is a chemical property? a.) ice melts at 0ºC b.)oxygen is a gas c.) helium is very nonreactive d.) sodium is a sof, shiny metal e.) water has a high specific heat
c.) helium is very nonreactive
a phosphide ion has: a.) 10 protons and 13 electrons b.)12 protons and 15 electrons c.) 15 protons and 15 electrons d.) 15 protons and 18 electros e.) 18 protons and 21 electrons
d.) 15 protons and 18 electrons
what are the two different ions present in the compound CaS a.) Ca+, S- b.) Ca^2-, S^2+ c.) Ca-, S+ d.) Ca^2+, S^2- e.) Ca, S
d.) Ca^2+, S^2-
give the formula for cobalt(II) chlorate dihydrate a.) CoCl 2 x 2H2O b.) CoClO3(H2O)2 c.) Co(ClO3)2(H2O)2 d.) Co(ClO3)2 x 2H2O e.) Co2(CLO3)3 x 2H2O
d.) Co(ClO3)2 • 2H2O
the chemical formula for iron(II) nitrate is a.) Fe2(NO3)3 b.) Ir(NO2)2 c.) Fe2N3 d.) Fe(NO3)2 e.) Fe(NO2)2
d.) Fe(NO3)2
the formula for magnesium sulfate is a.) MnS b.) MgS c.) MnSO3 d.) MgSO4 e.)MgSO3
d.) MgSO4
which is the formula for lead(IV) chloride a.) Pb4Cl b.) PbCl2 c.) PbCL3 d.) PbCl4 e.) Pb2Cl4
d.) PbCl4
which of the following processes require(s) chemical methods? a.) separating a homogeneous mixture into pure substance b.) separating a heterogeneous mixture into pure substance c.) distilling saltwater mixture d.) breaking a compound into its constituent elements e.) at least two of the above (a+d) require chemical methods
d.) breaking a compound into its constituent elements
which of the follow is NOT a step in the scientific method? a.)make an observation b.)formulate a hypothesis c.) perform an experiment d.) change results to agree w/your hypothesis e.) develop a theory (or model)
d.) change results to agree w/your hypothesis
which of the following involves a chemical change a.) boiling water b.) melting ice c.) chopping wood d.) cooking an egg
d.) cooking an egg
the name for CuSO4 x 5H2O a.)copper sulfate acid b.) copper sulfate pentahydrate c.)copper(II) sulfate acid d.) copper(II) sulfate pentahydrate e.) copper(V) sulfate hydrate
d.) copper(II) sulfate pentahydrate
what are the ions present in the compound CO2 a.)C^2+, 2 O- b.) C^2+, O^2- c.) C^2+, O2^2- d.) no ions present
d.) no ions present
an example of a mixture.... a.) hydrogen fluoride b.) purified water c.) gold d.) the air in the room e.) all above
d.) the air in the room
which of the following is a physical change? a.)burning gasoline b.)cooking an egg c.)decomposing meat d.)evaporating water e.)rusting iron
d.)evaporating water
in a chemical change... a.)a phase change must occur b.)the original material can never be regenerated c.)a phase change never occurs d.)the products are different substances from the starting materials
d.)the products are different substances from the starting materials
name the compound Cl2O5 = (Cl subscript 2 O subscript 5)
dichlorine pentoxide
which of the following elements is most likely to be a good conductor of electricity a.) N b.) S c.) He d.) Cl e.) Fe
e.) Fe
an example of a pure substance.... a.) elements b.) compounds c.) pure water d.) carbon dioxide e.) all above
e.) all above elements, compounds, pure water, carbon dioxide
the name for Ba(OH)2 a.)barium hydrogen oxide b.) boron hydroxide c.) barium hydrate d.) beryllium hydroxide e.) barium hydroxide
e.) barium hydroxide
name the compound CrO3 a.) chromium oxide b.) chromium(II) oxide c.) chromium(III) trioxide d.) chromium(III) oxide e.) chromium(VI) oxide
e.) chromium(VI) oxide
which describes a chemical property of gold? a.)gold is a yellow metal b.) gold is an inert (nonreactive) metal c.) gold is a soft metal d.)gold is very dense metal e.) gold is a good conductor of heat and electricity
e.) gold is a good conductor of heat and electricity
the name for KHCO3 a.) calcium bicarbonate b.) calcium carbonate c.) potassium carbonate d.) calcium hydrogen carbon trioxide e.) potassium hydrogen carbonate
e.) potassium hydrogen carbonate
which of the following is the formula for hydroiodic acid a.) HIO4 b.) HIO3 c.) HIO2 d.) HIO e.) HI
e.)HI
true or false? a compound can consist of one kind of element?
false
true or false? dry ice subliming (turning from solid to gas) is an example of a chemical change
false
true or false? gold is a relatively soft metal, which is a chemical property of the substance gold
false
true or false? the number of neutrons in all atoms of an element is the same?
false
the elements in a column of the periodic table are known as a
group
atoms of the same element with different mass numbers are called
isotopes
A___________ is a summary of observed behavior, and a___________ is an explanation of behavior
law, theory
a cubic centimeter (cm^3) is equivalent to what other metric volume unit
milliter
allotrope
one of two or more distinct form of an element ex. diamond and graphite are allotropes of diamond
name this binary compound; NaH
sodium hydride
which of the following is a pure compound? sodium, sugar, oxygen, air, iron
sugar
true of false? almost all the mass of an atom is concentrated in the nucleus
true
true or false? an empirical formula tell us which elements are present in a compound and gives us the simplest, whole-number ratio of the atoms of these elements in a compound
true
true or false? juice freezing into a popsicle is an example of a physical change
true
true or false? metal rusting is an example of a chemical change
true
true or false? the atomic number is equal to the number of protons in the nucleus of each atom of an element
true
true or false? the normal boiling point of water is 100ºC, which is a physical property of the substance water
true
express 1,220,000 in scientific notation
1.22 x 10^6
convert 1.4 mm = ______ km
1.4 x 10^ -6
what is the result of the following multiplication expressed in scientific notation to the correct number of significant figures? (2.08 • 10^5)(7.0 • 10^5-) =
1.5 • 10^1
convert 155.1 m. to decimeters
1.551 • 10^3 dm