chem 201 exam 2 (ch 4-7)
What is the mass % of acetonitrile in a 2.59 M solution of acetonitrile (MM = 41.05 g/mol) in water? The density of the solution is 0.810 g/mL.
13.1 % m
Percent by definition is parts per hundred. % (w/w) = (mass of solute/mass of solution) x 100. For very dilute solutions, chemists will often use parts per thousand or parts per million (ppm) or parts per billion (ppb). Calculate the concentration of a solution using each of these units. The legal limit of blood alcohol limit in most states is 0.080 grams per 100.0 grams of blood. What is this concentration in parts per million?
800 ppm
What is the mass in grams of H₂ that can be formed from 54.6 grams of NH₃ in the following reaction? 2 NH₃(g) → 3 H₂(g) + N₂(g)
9.6 g
Write the chemical formula for arsenic pentafluoride
AsF5
Polyatomic ion -2 charge
CO3-2,C8H4O4-2,SO4-2,SO3-2,CrO4-2,Cr3O7-2,C2O$-2,O2-2
Write the chemical formula for strontium perchlorate
Sr(clO4)2
Determine the correct formula for titanium(IV) chloride.
TiCl₄
What is the correct IUPAC name for BaI₂?
barium iodide
In a polar covalent bond,
one atom in the bond must have higher electronegativity than the other atom.
What numbers belong in the blank spaces to fully balance the following reaction? __Fe (s) + __Cl₂ (g) → __FeCl₃ (s)
2,3,2
Write the chemical formula for aluminum fluoride
AlF3
Which of the following bonds is a nonpolar covalent bond?
F-F
In the following chemical reaction, which element is the oxidizing agent? 3 Sn(NO₃)₂(aq) + 2 Fe(s) → 2 Fe(NO₃)₃(aq) + 3 Sn(s)
Sn
Which diatomic molecule has the smallest dipole moment?
all eqaul
Write the chemical formula for ammonium phosphide
(NH4)3p
Percent by definition is parts per hundred. % (w/w) = (mass of solute/mass of solution) x 100. For very dilute solutions, chemists will often use parts per thousand or parts per million (ppm) or parts per billion (ppb). Calculate the concentration of a solution using each of these units. The legal limit of blood alcohol limit in most states is 0.080 grams per 100.0 grams of blood. What is this concentration in parts per thousand?
0.8 ppt
What is the concentration of a solution made with 0.335 moles of KOH in 400.0 mL of solution?
0.838 M
What is the concentration of lithium ions in 0.430 M Li₂HPO₄?
0.86 M
Prefixes
1)mono, 2)di, 3)tri, 4)tetra, 5)penta, 6)hexa, 7)hepta, 8)octa, 9)nona, 10)deca
What is the mass in gram of NaCN in 12.00 mL of a 2.40 x 10-5 M solution
1.41x10-4 g NaCN
What volume (in mL) of 0.2600 M HBr is required to neutralize 40.00 mL of 0.8000 M NaOH?
123mL
Write a balanced chemical equation based on the following description: hydrogen gas reacts with oxygen gas to produce liquid water
2 H₂(g) + O₂(g) →2 H₂O(l)
If 35.0 g of CH₃OH (MM = 32.0 g/mol) are dissolved in 500.0 mL of solution, what is the concentration of CH₃OH in the solution?
2.18 M
Determine the amount in grams of KCl that exists in 20.3 g of a solution that contains 1.14 %KCl by mass
20.3 gKCl
What volume in mL of 0.300 M NaF would be required to make a 0.0495 M solution of NaF when diluted to 250.0 mL with water?
33.3 mL
Starting with the following equation, Fe₂O₃(s) + Al(s) → Fe(l) + Al₂O₃(s) calculate the moles of Fe₂O₃ that will be required to produce 645 grams of Fe.
5.8 mol
The oxidation number of Cl in HClO₄ is
7
What is the percent by weight (w/w%) of sugar in soda? Assume the average mass of sugar in soda is 36.0 g and the total mass is 370.0 g.
9.73 %
Write the balanced NET ionic equation for the reaction when aqueous BaCl₂ and aqueous (NH₄)₂SO₄ are mixed in solution to form aqueous NH₄Cl and solid BaSO₄.
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Which atom in the Br-F molecule has a partial positive charge (δ⁺)?
Br
Which atom in the C-Br bond has a partial negative charge (δ⁻)?
Br
Write the chemical formula for the hypobromite ion
BrO-
Based on their positions in the periodic table, which of the following bonds is the most polar?
C-F
Write the chemical formula for the acetate ion
CH3COO-
Write the chemical formula for the dichromate ion
Cr2O72-
Complete the balanced dissociation equation for the compound below in aqueous solution. If the compound does not dissociate, write NR after the reaction arrow.
Cs₂CO₃(s) → 2 Cs⁺(aq) + CO₃²⁻(aq)
What is the molecular formula of a compound that contains only carbon and hydrogen, is 85.6% carbon, and has a molar mass of 70 g/mol?
C₅H₁₀
A compound that contains only carbon, hydrogen, and oxygen is 58.8% C and 9.87% H by mass. What is the empirical formula of this substance?
C₅H₁₀O₂
A compound containing Na, C, and O is found to have 1.06 mol Na, 0.528 mol C, and 1.59 mol O. What is the empirical formula of the compound?
D) Na₂CO₃
Write a balanced chemical equation based on the following description: the reaction of solid iron(III) sulfide with aqueous hydrochloric acid to form aqueous iron(III) chloride and hydrogen sulfide gas.
Fe₂S₃(s) + 6HCl(aq) → 2FeCl₃(aq) + 3H₂S(g)
Complete the balanced neutralization equation for the reaction below:
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
What are the reactants in the following equation: HCl(aq) + NaHCO₃(aq)→ CO₂(g) + H₂O(l) + NaCl(aq)
HCl, NaHCO₃
Complete the balanced neutralization equation for the reaction below:
HClO₄(aq) + CsOH(aq) → CsClO₄(aq) + H₂O(l)
Determine the correct formula for manganese(II) fluoride
MnF₂
Write the chemical formula for dinitrogen tetroxide
N2O4
Polyatomic ion +1 charge
NH4+1
Write the chemical formula for sodium sulfite
Na2SO3
Polyatomic ion -3 Charge
PO4-3,PO3-3,AsO4-3
transition
Roman numerals in the middle
If you are given the molarity of a solution, what additional information would you need to find the weight/volume percent (w/v%)?
The molar mass of the solute
What is the correct IUPAC name for AlN?
aluminum nitride
What is the correct IUPAC name for AlPO₄?
aluminum phosphate
What is the correct IUPAC name for CaBr₂?
calcium bromide
What is the correct IUPAC name for CrBr₃?
chromium (III) bromide
What is the correct IUPAC name for Co(NO₂)₂?
cobalt (II) nitrite
What is the correct IUPAC name for CoPO₄?
cobalt (III) phosphate
What is the correct IUPAC name for CoCl₂ ?
cobalt(II) chloride
What is the correct IUPAC name for Cl₂O₇?
dichlorine heptoxide
What is the correct IUPAC name for Fe(HSO₄)₃?
iron (III) hydrogen sulfate
diamagnetic
paired electrons
What is the correct IUPAC name for AgI?
silver iodide
The maximum amount of possible product formed in a reaction if the limiting reactant is completely converted to product is called the _________.
theoretical yield
What is the concentration in molarity of a solution which is 3.63 %m/v benzene (C₆H₆, MM =78.11 g/mol ) in CCl₄ (MM = 153.81 g/mol)?
0.465 M
What is the correct formula for cobalt(III) hydroxide?
Co(OH)₃
What is the correct IUPAC name for As₂S₅?
arsenic pentasulfide
The best reason for why a covalent bond forms is
atoms with high electronegativities will not lose electrons, so instead they share electrons to reach a stable number of valence electrons.
What is the correct IUPAC name for Ca(NO₃)₂?
calcium nitrate
what is the correct IUPAC name for CuIO?
copper (I) hypoiodite
What is the correct IUPAC name for Mg₃(PO₄)₂
magnesium phosphate
What is the correct IUPAC name for AgNO₂?
silver nitrite
Hybridization
single bond =1 double bond =1 triplet bond =1 lone pair=1 2=sp 3=sp2 4=sp3
The reason an ionic bond forms can best be described as
the energy change for electron transfer results in a large gain in stability when the ionic bond forms.
What is the correct IUPAC name for TiCl₄?
titanium (IV) chloride
What is the correct IUPAC name for Ti(ClO₄)₄?
titanium (IV) perchlorate
Water is a polar molecule because
water is a bent molecule and oxygen is more electronegative than hydrogen.
Which atom in the C-Br bond has a partial positive charge (δ⁺)?
C
Adding electrons to bonding molecular orbitals will:
Increase the bond order
Write the balanced equation for the reaction of solid potassium chlorate decomposing to form solid potassium chloride and oxygen gas.
2 KClO₃ (s) → 2 KCl (s) + 3 O₂ (g)
Starting with the following equation, BCl₃(g) + LiAlH₄(s) → B₂H₆(g) + LiAlCl₄(s) calculate the moles of BCl₃ that will be required to produce 365 grams of B₂H₆.
26.45 mol
How many π bonds are in the structure of the organic molecule below?
4
Write a balanced chemical equation based on the following description: iron metal reacts with oxygen gas to produce solid iron(III) oxide
4 Fe(s) + 3 O₂(g) → 2 Fe₂O₃(s)
What is the mass percentage of C in caffeine, C₈H₁₀N₄O₂? Provide an answer to two decimal places
49.48%
The reactant in a chemical reaction that is the first to be used up is called _________.
limiting reactant
500.0 mL of a 0.300 M solution of LiBr is diluted to 700.0 mL. What is the new concentration of the solution?
0.214 M
Balance the following chemical equation (if necessary) for the combustion reaction of glucose:
C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(g)
Write the balanced COMPLETE ionic equation for the reaction when copper(II) sulfate and ammonium nitrate are mixed in aqueous solution. If no reaction occurs, simply write only NR.
NR
Which of the following bonds is the most polar?
Rb-Br
What is the correct IUPAC name for PbF₂?
lead (II) fluoride
What volume (in L) of 1.10 M FeCl₃ would be required to obtain 0.620 moles of Cl⁻ ions?
0.19 L
Which one of the following statements best describes electronegativity in atoms?
Electronegativity is the attraction an element's nucleus has for the electrons in a chemical bond.
What is the correct IUPAC name for Pb(ClO₂)₂?
lead (II) chlorite
Polyatomic ion -1 charge
BrO4-1, BrO3-1, BrO2-1, BrO-1, ClO4-1,ClO3-1,ClO2-1,ClO-1,IO4-1,IO3-1,IO2-1,IO-1,NO3-1,NO2-1,OH-1,CN-1,SCN-1,C2H3O2-1,MnO4-1,HCO3-1
Write the balanced NET ionic equation for the reaction when (NH₄)₂CO₃ and CaCl₂ are mixed in aqueous solution. If no reaction occurs, simply write only NR.
Ca²⁺(aq) + CO₃²⁻(aq) → CaCO₃(s)
To make a s'more snack, it takes 2 marshmallows, 1/3 of chocolate bar, and 1 graham cracker. However, these ingredients are sold in ratios that do not allow you to use up all of the ingredients. Based on the packaging of the ingredients (shown below), what is the limiting reagent?
Chocolate (50 giant marshallows, 16 graham, 5 chocolate)
Which of the following is an example of a covalent bond?
H - Cl
Which of the following bonds is a polar covalent bond?
H-Cl
Which of the following molecules is considered least stable according to molecular orbital theory?
He2
Complete the balanced neutralization equation for the reaction below:
H₂SO₄(aq) + Mg(OH)₂(aq) → MgSO₄(aq) + 2 H₂O(l)
What does the ring in the center of a benzene molecule represent?
It means the π electrons are delocalized around the benzene ring
Write the chemical formula for potassium dichromate
K2Cr2O7
What is the correct IUPAC name for BrCl₃?
bromine trichloride
What is the correct IUPAC name for CBr₄?
carbon tetrabromide
ionic
metal and nonmetal, transfer of electrons
Which group in the periodic table tends to have high electronegativity values?
the halogens
Which of the following best describes what happens when an ionic bond forms?
two atoms, one atom which is more electronegative than the other, exchange electrons and the charges hold the atoms together.
paramagnetic
unpaired electrons
A molecule that contains delocalized electrons _____
will have at least two resonance structures
The oxidation number of a phosphorus atom in P₄ is
0
The oxidation number of the phosphorus atom in P³⁻ is
0
If you have 1 mol Xe and 1 mol F₂, how many moles of XeF₄ can you create in the following chemical reaction? Xe (g) + 2 F₂ (g) → XeF₄ (g)
0.5 mol
If 2.00 moles of H₂ and 1.55 moles of O₂ react how many moles of H₂O can be produced in the reaction below? 2 H₂(g) + O₂(g) → 2 H₂O(g)
2 mol
You have 2.2 mol Xe and 2.0 mol F₂, but when you carry out the reaction you end up with only 0.25 mol XeF₄. What is the percent yield of this experiment? Xe(g) + 2 F₂ (g) → XeF₄ (g)
25 %
What volume of 0.220 M HBr solution (in mL) is required to obtain 0.0600 moles of HBr?
273 mL
Write the balanced COMPLETE ionic equation for the reaction when CaCl₂ and Na₃PO₄ are mixed in aqueous solution. If no reaction occurs, simply write only NR.
3 Ca²⁺(aq) + 6 Cl⁻(aq) + 6 Na⁺(aq) + 2 PO₄³⁻(aq) → 6 Na⁺(aq) + 6 Cl⁻(aq) + Ca₃(PO₄)₂(s)
Starting with the following equation, Fe₃O₄(s) + CO(g) → Fe(l) + CO₂(g) calculate the mass in grams of Fe₃O₄ that will be required to produce 225 grams of Fe.
311 g
Sucrose (C₁₂H₂₂O₁₁) is combusted in air according to the following reaction: C₁₂H₂₂O₁₁(s) + O₂(g) → CO₂(g) + H₂O(l) How many grams of carbon dioxide would be produced by the complete combustion of 0.755 moles of sucrose in the presence of excess oxygen?
399 g
What is the mass in grams of NO that can be formed from 4.96 moles of NO₂ in the reaction below? 3 NO₂ (g) + H₂O (g) → 2 HNO₃ (g) + NO (g)
49.62 g
How many moles of CH₃OH are there in 64.0 mL of 0.400 M CH₃OH?
0.026 mol
What quantity in moles of HCl are there in 79.5 mL of 0.350 M HCl?
0.028 mol
Convert the concentration of 0.700 M Na2SO4 to g/ml
0.0994 g Na2SO4/mL
100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. What is the new concentration of the solution?
0.100 M
How many moles of ammonia would be required to react exactly with 0.470 moles of copper(II) oxide in the following chemical reaction? 2 NH₃(g) + 3 CuO(s) → 3 Cu(s) + N₂(g) + 3 H₂O(g)
0.313 mol
What quantity in moles of NaOH are there in 140.0 mL of 2.50 M NaOH?
0.350 mol
Write the balanced COMPLETE ionic equation for the reaction when Li₂CO₃ and Co(C₂H₃O₂)₂ are mixed in aqueous solution. If no reaction occurs, simply write only NR.
2 Li⁺(aq) + CO₃(aq)²⁻ + Co²⁺(aq) + 2 C₂H₃O₂⁻(aq) → CoCO₃ (s) + 2 Li⁺(aq) + 2 C₂H₃O₂⁻(aq)
Write the balanced NET ionic equation for the reaction when aqueous (NH₄)₃PO₄ and aqueous Zn(NO₃)₂ are mixed in solution to form solid Zn₃(PO₄)₂ and aqueous NH₄NO₃.
2 PO₄³⁻(aq) + 3 Zn²⁺(aq) → Zn₃(PO₄)₂(s)
To what volume (in mL) would you need to dilute 45.0 mL of a 1.20 M solution of NaBr to make a 0.0230 M solution of NaBr?
2350 mL
The oxidation number of a nitrogen atom in N₂O₃ is
3
The oxidation number of aluminum in Al³⁺ is
3
Complete the balanced neutralization equation for the reaction below:
3 NH₄OH(aq) + H₃PO₄(aq) → (NH₄)₃PO₄(aq) + 3 H₂O(l)
What is the mass percent of water in Ca(NO₃)₂･4 H₂O? Provide an answer to two decimal places.
30.52%
Ethanol (C₂H₆O) is combusted in air according to the following reaction: C₂H₆O(l) + O₂(g) → CO₂(g) + H₂O(l) How many grams of water would be produced by the complete combustion of 6.45 moles of ethanol in the presence of excess oxygen?
349 g
Percent by definition is parts per hundred. % (w/w) = (mass of solute/mass of solution) x 100. For very dilute solutions, chemists will often use parts per thousand or parts per million (ppm) or parts per billion (ppb). Calculate the concentration of a solution using each of these units. The legal limit of blood alcohol limit in most states is 0.080 grams per 100.0 grams of blood. What is this concentration in parts per billion?
800000 ppb
What is the difference between actual yield and theoretical yield?
Actual yield is how much is actually produced in a reaction (it has to be given or measured), and theoretical yield is a calculation that has to be done.
In the following chemical reaction, which element is the reducing agent? 2 IO₃⁻(aq) + 12 H⁺(aq) + 10 Ag(s) + 10 Cl⁻(aq) → 10 AgCl(s) + I₂(s) + 6H₂O(l)
Ag
Complete the balanced dissociation equation for the compound below in aqueous solution. If the compound does not dissociate, write NR after the reaction arrow.
AgNO₃(s) → Ag⁺(aq) + NO₃⁻(aq)
Write the chemical formula for aluminum perbromate
Al(BrO4)3
Balance the following chemical reaction: Al₂(SO₄)₃ (aq) + K₃PO₄ (aq) → AlPO₄ (s) + K₂SO₄ (aq)
Al₂(SO₄)₃ (aq) + 2 K₃PO₄ (aq) → 2 AlPO₄ (s) + 3 K₂SO₄ (aq)
Complete the balanced dissociation equation for the compound below in aqueous solution. If the compound does not dissociate, write NR after the reaction arrow.
Al₂(SO₄)₃(s) → 2 Al³⁺(aq) + 3 SO₄²⁻(aq)
What are the oxidation numbers of each element in the arsenate ion, AsO₄³⁻?
As = +5, O = -2
Write the chemical formula for the carbonate ion
CO32-
What is the correct formula for calcium oxide?
CaO
Write the chemical formula for dichlorine heptoxide
Cl2O7
Which atom in the Br-F molecule has a partial negative charge (δ⁻)?
F
Which diatomic molecule has the largest dipole moment?
HF
The molecule HI is:
Heteronuclear
An aqueous solution of Mg(NO₃)₂ and NaOH generates the solid precipitate Mg(OH)₂. Which of the following would NOT appear in the corresponding net ionic reaction?
NO₃⁻
Write the chemical formula for nickel(II) iodide
NiI2
Complete the balanced molecular chemical equation for the reaction below. If no reaction occurs, write NR after the reaction arrow.
Pb(NO₃)₂(aq) + 2 KI(aq) → PbI₂(s) + 2 KNO₃(aq)
Write the chemical formula for disulfur decafluoride
S2F10
Which one of the following has the smallest mass percent of F in the compound?
XeF₂ (19.00g×2)/(19.00g×2)+131.29g×100=22.4%
What is the correct IUPAC name for CuNO₃?
copper (I) nitrate
What is the correct IUPAC name for CuSO₃?
copper (II) sulfite
What is the correct IUPAC name for S₂F₈?
disulfur octafluoride
The term 'delocalization' refers to
electrons being shared via π bonds between more than just two atoms.
covalent
nonmetal and nonmetal
What is the correct IUPAC name for KClO₃?
potassium chlorate
In a covalent bond
two atoms share valence electrons and those shared electrons form the chemical bond.
A π bond could be formed from the overlap of which two orbitals?
two unhybridized p orbitals
A more electronegative atom
will have more attraction to the electrons in a chemical bond.
Which one of the following bonds has the least ionic character?
B-Cl
Write the balanced dissociation equation for solid cesium phosphate in aqueous solution. If it does not dissociate, simply write only NR.
Cs₃PO₄(s) → 3 Cs⁺(aq) + PO₄³⁻(aq)
Write a balanced chemical equation based on the following description: the reaction of gaseous C₅H₄ with oxygen gas produces gaseous carbon dioxide and water vapor
C₅H₄(g) + 6 O₂(g) → 5 CO₂(g) + 2 H₂O(g)
What is the empirical formula of acetic acid, HC₂H₃O₂?
H₂CO (H4/2=2,C2/2=1,O2/2=1)
Bo=1/2(#of bond electron-#of a antibonding electron)
I2 (7x2=14) 8-6/2=1 π σ ( bond) π* σ* (antibonding)
Which of the following is an example of an ionic bond?
K-F
In the following reaction, which element in what species is oxidized? Au(NO₃)₃ (aq) + 3 Li(s) → Au(s) + 3 LiNO₃ (aq)
Li
What is the correct formula for lithium chlorate?
LiClO₃
Which one of the following statements is FALSE?
Linear molecules cannot have a net dipole moment
