Chemistry Final (Web assign) edition
When an atom forms a cation, the ion is
negatively charged. larger than the original atom. the same size as the original atom. correct smaller than the original atom.
What is a vertical column in the periodic table called?
period set correct family octet
Which of the following types of compound dissolve in a nonpolar solvent? (Select all that apply.)
polar molecular correct nonpolar molecular network-covalent metallic ionic
To which family do magnesium and calcium belong?
transition metals halogens correct alkaline earth metals noble gases alkali metals
Which element has similar properties to Mg?
A) Li B) correct: Sr C) Al D) Na
Calculate the number of molecules present in each of the following samples.
(a) 0.600 mol propane, C3H8, a gas used in laboratories 3.61e+23 molecules (b) a 250 mg tablet of CaCO3, an antacid 1.50e+21 molecules (c) a water droplet containing 2.00 10-5 g of H2O. 6.68e+17 molecules
Balance the following chemical equations. (Use the smallest possible whole numbers. Enter 1 where appropriate. Do not leave any answer box blank.)
(a) 1 Ca3P2(aq) + 6 H2O(l) ---> 3 Ca(OH)2(aq) + 2 PH3(aq) (b) 1 P2O5(s) + 3 H2O(l) ---> 2 H3PO4(aq) (c) 1 MnO2(s) + 4 HCl(aq) ---> 1 MnCl2(aq) + 1 Cl2(g) + 2 H2O(l)
Balance the following chemical equations and indicate the type of each reaction. (Use the smallest possible whole numbers. Enter 1 where appropriate. Do not leave any answer box blank.)
(a) 2 C3H6(g) + 9 O2(g) ---> 6 CO2(g) + 6 H2O(l) correct combustion decomposition single replacement double replacement synthesis (b) 1 NH4NO3(s) ---> 1 N2O(g) + 2 H2O(l) combustion correct decomposition single replacement double replacement synthesis (c) 1 N2(g) + 3 H2(g) ---> 2 NH3(g) combustion decomposition single replacement double replacement correct synthesis (d) 1 K2O(s) + 1 H2O(l) ---> 2 KOH(aq) combustion decomposition single replacement double replacement correct synthesis
Balance the following chemical equations. (Use the smallest possible whole numbers. Enter 1 where appropriate. Do not leave any answer box blank.)
(a) 2 Fe(s) + 3 Cl2(g) ---> 2 FeCl3(s) (b) 4 NH3(g) + 5 O2(g) ---> 4 NO(g) + 6 H2O(g) (c) 1 Mg(s) + 2 HCl(aq) ---> 1 MgCl2(aq) + 1 H2(g)
Classify the following reactions.
(a) Cl2(g) + 2 NaBr(s)---> Br2(g) + 2 NaCl(s) double replacement synthesis combustion correct single replacement decomposition (b) 8 Fe(s) + S8(s) ---> 8 FeS(s) double replacement correct synthesis combustion single replacement decomposition (c) C2H5OH(l) + 3 O2(g) ---> 2 CO2(g) + 3 H2O(g) double replacement synthesis correct combustion single replacement decomposition
Classify the following reactions.
(a) CuCl2(aq) + 2 NaOH(aq) ---> Cu(OH)2(s) + 2 NaCl(aq) correct double replacement synthesis combustion single replacement decomposition (b) 2 KClO3(aq) ---> 2 KCl(aq) + 3 O2(g) double replacement synthesis correct combustion single replacement correct decomposition (c) C3H8(g) + 5 O2(g) ---> 3 CO2(g) + 4 H2O(g) double replacement synthesis correct combustion single replacement decomposition
(a) Jewelry sometimes features diamonds, a form of pure carbon. How many moles of carbon are in a 3.60 carat diamond (1 carat = 0.200 g)? (b) The molecular formula of acetylsalicylic acid (aspirin), originally derived from the willow tree, is C9H8O4. How many moles of C9H8O4 molecules are in a 125. mg caplet of aspirin?
(a) Jewelry sometimes features diamonds, a form of pure carbon. How many moles of carbon are in a 3.60 carat diamond (1 carat = 0.200 g)? 0.0600 mol C How many atoms compose the diamond? 3.61e+22 C atoms (b) The molecular formula of acetylsalicylic acid (aspirin), originally derived from the willow tree, is C9H8O4. How many moles of C9H8O4 molecules are in a 125. mg caplet of aspirin? 0.000694 mol C9H8O4 How many molecules of C9H8O4 are in this caplet? 4.18e+20 C9H8O4 molecules
Select the type of bonding exhibited in the substances listed below.
(a) NH4Cl both: covalent & Ionic (b) BCl3 covalent (c) Ba(OH)2 both: covenant & Ionic (d) SF6 covalent (e) ClO2 covalent (f) MgSO4 both
For each of the following pairs, indicate which element has the larger atomic radius.
(a) Na (b) Ca (c) In (d) O (e) I (f) Ba (g) Al (h) Au
Plot the boiling points and melting points of water, ethanol, bromine and radon using the information provided in the table of data. Graph temperature on the Y axis and the compounds on the X axis. (Do this on paper. Your instructor may ask you to turn in this work.) Substance Melting point Boiling point water 0°C 100°C ethanol -115°C 78°C bromine -7°C 59°C radon -71°C -61°C
(a) What is the lowest temperature that all four substances can exist as a gas? 100 °C (b) Which substance can not exist as a gas at a temperature of 90.0°C water (c) Which substance cannot exist as a liquid at a temperature of 10.0°C radon (d) What is the highest temperature that all four substances can exist as a solid? -115 °C
Classify the following as homogenous mixtures, heterogenous mixtures, elements or compounds.
(a) dry soup mix A) compound B) homogenous mixture C) element D) correct: heterogenous mixture (b) water A) element B) correct: compound C) homogenous mixture D) heterogenous mixture (c) salad dressing A) correct: heterogenous mixture B) homogenous mixture C) compound D) element (d) magnesium oxide correct compound element heterogenous mixture homogenous mixture Incorrect: Your answer is incorrect. (e) salt water A) element B) heterogenous mixture C) compound D) correct: homogenous mixture
Calculate the mass percentage (to one decimal place) of each of the following.
(a) sulfur in carbon disulfide, CS2 84.2 % (b) hydrogen in ammonium chloride, NH4Cl 7.48 % (c) sulfur in zinc sulfate, ZnSO4 19.9 %
Calculate the mass of 1.65 ✕ 1020 molecules of N2O5. Use a molar mass with at least as many significant figures as the data given.
0.0296 g
2 MnO(s) + 5 PbO2(s) + 10 HNO3(aq) ---> 2 HMnO4(aq) + 5 Pb(NO3)2(aq) + 4 H2O(l) Manganese(II) oxide, lead(IV) oxide, and nitric acid react to produce permanganic acid, lead(II) nitrate, and water according to the reaction above. How many moles of each product could be produced by the reaction of 3.20 moles of nitric acid with excess manganese(II) oxide and excess lead(IV) oxide?
0.640 mol HMnO4 1.60 mol Pb(NO3)2 1.28 mol H2O
Al(OH)3(s) + 3 HCl(aq) ---> AlCl3(aq) + 3 H2O(l) Some brands of antacid tablets have used aluminum hydroxide to neutralize excess acid, as shown above. How many grams of HCl can a tablet with 0.635 g of Al(OH)3 consume?
0.890 g What mass of water is produced? 0.440 g
What is the correct Lewis electron-dot structure for the compound magnesium fluoride?
1 2 correct 3 4 [:F:] Mg2+ [:F:] two dots on both the top and the bottom of both F's in [ ] (Flouride)
A neutral atom contains 12 neutrons and 11 electrons. What is the number of protons in this atom?
1 correct 11 23 12
Calculate the number of molecules of H2O in 30.5 g of H2O. Use a molar mass with at least as many significant figures as the data given.
1.02e+24 molecules
How many grams are in 1.120 kilograms? Enter your answer using standard scientific or "e" notation and the correct number of significant figures (for example, 105 = 1.05e2).
1.120e3 g
How many moles of chromium are in 83.2 g of Cr ore that is 74.4% pure?
1.19 mol Cr
Calculate the number of molecules of C6H3(NO2)3 in 46.5 g C6H3(NO2)3. Use a molar mass with at least as many significant figures as the data given.
1.31e+23 molecules
What is the frequency of a photon with a wavelength of 2.25 ✕ 102 nm? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626✕ 10-34 J · s.
1.33e+15 s-1
Calculate the number of moles of C2H5OH in 65.0 g of C2H5OH . Use a molar mass with at least as many significant figures as the data given.
1.41 mol
What is the energy of a photon with a wavelength of 1.25 ✕ 103 nm? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626 ✕ 10-34 J·s.)
1.59e-19 J
2 NaClO3 ---> 2 NaCl + 3 O2 Determine the number of moles of O2 produced by the decomposition of 745 g of NaClO3.
10.5 mol
Calculate the mass of 7.90 ✕ 1025 molecules of C6H14. Use a molar mass with at least as many significant figures as the data given.
11300 g
What is the approximate mass of 1.23 liters of water?
12300 g 1.23 g 12.30 g correct 1230 g 1230.00 g
Calculate the mass of 0.170 moles of SO3. Use a molar mass with at least as many significant figures as the data given.
13.6 g
What is the percentage of carbon (to one decimal place) in NaHCO3?
14.3 %
What is the energy of a photon with a wavelength of 8.25 ✕ 103 nm? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626 ✕ 10-34 J · s.)
14.5 kJ/mol
What is the total number of protons in the nucleus of an atom of potassium-42?
15 correct 19 39 42
How many significant zeros are in 0.002030?
2 -or- two
Which of the following do not represent a single replacement reaction? (Select all that apply.)
2 Al(s) + 3 CuCl2(aq)---> 2 AlCl3(aq) + 3 Cu(s) correct 2 C2H6(g) + 7 O2(g) ---> 4 CO2(g) + 6 H2O(g) 2 Li(s) + 2 H2O(l) ---> 2 LiOH(aq) + H2(g) 2 HCl(aq) + Mg(s) ---> MgCl2(aq) + H2(g)
Convert 250.0 cm to meters. Enter the correct number of significant figures.
2.500 -or- 2.500e0 m
Calculate the value of the following in exponential form, using standard scientific or "e" notation (for example, 105 = 1.05e2). Enter the correct number of significant figures. 235.15 cm + 9.2 cm + 35.111 cm
2.795e2 cm
Calculate the value of the following in exponential form, using standard scientific or "e" notation (for example, 105 = 1.05e2). Enter the correct number of significant figures. (6.555e-3 cm)3 / (0.010 cm)
2.8e-5 cm2
Calculate the number of molecules of CO2 in 21.5 g of CO2. Use a molar mass with at least as many significant figures as the data given.
2.94e+23 molecules
The gram formula mass of NH4Cl is
22.4 g/mole 28.0 g/mole correct 53.5 g/mole 95.5 g/mole
CH4 + 2 O2 ---> CO2 + 2 H2O How many grams of CO2 are formed from the combustion of 5.00 moles of methane, CH4, in oxygen?
220. g
Convert 65.5 cm to inches. Report the answer to the correct number of significant figures. (1 inch = 2.54 cm is an exact or defined conversion.)
25.8 in.
What is the total number of electrons in a Cr3+ ion?
27 18 24 correct 21
Convert 17.0 in3 to cm3. Report the answer to the correct number of significant figures. (1 inch = 2.54 cm is an exact or defined conversion.)
279 cm3
Potassium chlorate is a rich source of oxygen. It decomposes upon heating to produce potassium chloride and oxygen. Write a correctly balanced equation for this reaction. (Use the smallest whole numbers possible. Type your answers using the format 2Ca(OH)2 for 2 Ca(OH)2.)
2KClO3 (s) ---> 2KCl (s) + 3O2 (g)
How many significant zeros are in .0650030?
3 -or- three
Calculate the value of the following in exponential form, using standard scientific or "e" notation (for example, 105 = 1.05e2). Enter the correct number of significant figures. (9.55e2 cm)2 / (2.5e-2 cm)
3.6e7 cm
Express .0370700 in exponential form, using standard scientific or "e" notation (for example, 105 = 1.05e2). Enter the correct number of significant figures.
3.70700e-2
Calculate the mass of 0.350 moles of Fe(OH)3. Use a molar mass with at least as many significant figures as the data given.
37.5 g
What is the total number of oxygen atoms in the formula MgSO4·7 H2O? [The·represents seven units of H2O attached to one unit of MgSO4.]
4 5 7 correct 11
The density of sulfur (S) is 2.07 g/cm3 and the density of tellurium (Te) is 6.24 g/cm3. Estimate the density of selenium (Se).
4.16 g/cm3
Calculate the mass of 6.85 ✕ 1023 molecules of C4H10. Use a molar mass with at least as many significant figures as the data given.
66.0 g
Fe2O3(s) + CO(g) ---> Fe(l) + CO2(g) How many grams of Fe2O3(s) will be required to produce 8.30 moles of Fe(l)? Hint: Be sure to balance the equation first!
663 g
How many valence electrons are in an atom having the electron configuartion 1s22s22p63s23p64s23d5?
7 5 13 correct 2
What is the wavelength of a photon with a frequency of 4.10 ✕ 1014 s-1? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626 ✕ 10-34 J · s.)
7.31e-07 m
What is the energy of a photon emitted by the 6 to 4 transition in a hydrogen atom? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626 ✕ 10-34 J·s. The Bohr constant, BH, is 2.18 ✕ 10-18 J. The Rydberg constant, RH, is 1.097 ✕ 107 m-1.)
7.57e-20 J What is the wavelength of the photon emitted, in meters and nanometers? 2.62e-06 m 2620 nm
The data table below represents the properties determined by the analysis of substances A, B, C, and D. Substance Melting Point(C) Boiling Point(C) Conductivity A -80 -20 none B 20 190 none C 320 770 as solid D 800 1250 in solution Which substance is an ionic compound?
A B C correct D
What does the metric prefix milli mean?
A) 1/100 B) 1000 times C) 100 times D) correct: 1/1000
What does the metric prefix kilo mean?
A) 100 times larger B) 1000 times smaller C) correct: 1000 times larger D) 100 times smaller
The concept of ____ indicates the ability of a person to measure consistently.
A) accuracy B) correct: precision C) usefulness D: statistically
To which family do sodium and potassium belong?
A) alkaline earth metals B) correct: alkali metals C) transition metals D) halogens
To which family do argon and helium belong?
A) alkaline earth metals B) halogens C) transition metals D) correct: noble gases
A student measures mass and volume for an unknown substance as well as some known substances. Data is shown below. Substance Mass(g) Volume(cm3) aluminum 33.8 12.5 iron 135.4 4.65 lead 32.0 2.85 tin 25.0 3.44 unknown 33.8 4.65 Based on the data obtained, what is the unknown substance likely to be?
A) aluminum B) iron C) correct: tin D) lead
How many centimeters are in 25.0 kilometers?
A) correct: 2.50 ✕ 106 cm B: 2.50 ✕ 105 cm C: 2.50 ✕ 104 cm D: 2.50 ✕ 103 cm E: 2.50 ✕ 107 cm
How many kilometers are in 6,250,000.0 centimeters?
A) correct: 6.2500000 ✕ 101 km B) 62.5 ✕ 101 km C) 6.25 ✕ 101 km D) 6.25 ✕ 107 km E) 6.2500000 ✕ 107 km
Convert 7.000 ✕ 106 cubic centimeters to liters.
A) correct: 7.000 ✕ 103 L B) 7.000 ✕ 108 L C) 7.000 ✕ 106 L D) 7.000 ✕ 104 L
Convert 8.0 ✕ 109 mg to kilograms.
A) correct: 8.0 ✕ 103 kg B) 8.0 ✕ 106 kg C) 8.0 ✕ 109 kg D) 8.0 ✕ 1015 kg
To which family do fluorine and bromine belong?
A) correct: halogens B) alkaline earth metals C) alkali metals D) noble gases
Select the correct number of significant figures for 0.0230.
A) correct: three B) six C) one D) two E) five F) four
The modern periodic law states that properties of elements are periodic functions of their
A) densities B) number of neutrons C) correct: atomic numbers D) atomic masses
The modern periodic law allows one to predict properties of an element based on its
A) number of neutrons B) correct: position in the periodic table C) symbol D) number of isotopes
What is a horizontal row of elements in the periodic table called?
A) octet B) correct: period C) family D) group
Select the correct number of significant figures for 1500 grams of copper (II) chloride.
A) one B) four C) five D) three E) correct: two F) six
The concept of ____ indicates how close the experimental answer is to the true value.
A) precision B) replicable C) usefulness D) correct: accuracy
Which elements are characterized by the filling of d orbitals?
A) rare earths B) correct: transition metals C) alkali metals D) halogens
What is a vertical column in the periodic table called?
A) set B) correct family C) period D) octet
Select the correct number of significant figures for 0.05000 m of copper wire.
A) two B) five C) three D) one E) six F) correct: four
Select the correct number of significant figures for 0.1000 mg of sodium chloride.
A) two B) three C) five D) one E) correct: four
What is the formula for silver chloride?
Ag2Cl AgCl2 correct AgCl AgCl3
The formula for zinc phosphide is Zn3P2. What is the formula of cadmium nitride? Enter the formula in the form of the element symbol followed by the subscript such as MgCl2 or N2O5.
CdN Cd2N2 CdN2 correct Cd3N2 Cd2N3
Which one of the following atoms has the largest radius?
Cl F correct S O
Which element has the lowest first ionization energy?
Ar correct K Ca Cl
Which statement best explains why most atomic masses on the Periodic Table are decimal numbers?
Atomic masses are determined relative to an O-16 standard. correct Atomic masses are a weighted average of the naturally occurring isotopes. Atomic masses are determined relative to an H-1 standard. Atomic masses are an estimated average of the artificially produced isotopes.
For the following combination of reactants, enter the formulae of the products in the space provided and give their physical states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) Bi2(CO3)5(s) + HBr(aq)--->
Bi2(CO3)5(s) + HBr(aq)---> BiBr5(aq), H2O(l), CO2(g) -or- BiBr5(aq), CO2(g), H2O(l) -or- H2O(l), CO2(g), BiBr5(aq) -or- H2O(l), BiBr5(aq), CO2(g) -or- CO2(g), H2O(l), BiBr5(aq) -or- CO2(g), BiBr5(aq), H2O(l) What type of reaction is this? What type of reaction is this? combustion decomposition single replacement correct double replacement synthesis
Metallic bonding exists in which of the following? (Select all that apply.)
C (diamond) correct iron water MgO nitrogen
Using the VSEPR theory, which of the following molecules exhibit linear molecular geometry. (Select all that apply.)
CH4 SiF4 correct HCl PCl5 H2O correct CO2
Which of the following elements has the highest electronegativity?
Ca correct H Al K
The formula for magnesium chloride is MgCl2. What is the formula of calcium fluoride? Enter the formula in the form of the element symbol followed by the subscript such as MgCl2 or N2O5.
Ca2F2 correct CaF2 CaF Ca2F
What is the formula for calcium hydroxide?
Ca2OH CaOH2 CaOH correct Ca(OH)2
Which molecule contains a triple covalent bond?
Cl2 H2 correct N2 O2
What is the formula for copper (I) sulfate?
CuSO4 Cu2SO3 correct Cu2SO4 Cu2S
For the following combination of reactants, enter the formulae of the products in the space provided and give their states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) Fe2(SO4)3(aq) + CaCl2(aq) --->
Fe2(SO4)3(aq) + CaCl2(aq) ---> CaSO4(s), FeCl3(aq) -or- FeCl3(aq), CaSO4(s) What type of reaction is this? combustion decomposition single replacement correct double replacement synthesis
Classify each of the following reactions.
FeCl2 + 2 AgNO3---> Fe(NO3)2 + 2 AgCl combustion decomposition single replacement correct double replacement synthesis C2H6O + 3 O2 ---> 2 CO2 + 3 H2O correct combustion decomposition single replacement double replacement synthesis SrCO3 + heat ---> SrO + CO2 combustion correct decomposition single replacement double replacement synthesis 2 K + 2 H2O ---> 2 KOH + H2 combustion decomposition correct single replacement double replacement synthesis 3 Br2 + 2 Al---> 2 AlBr3 combustion decomposition single replacement double replacement correct synthesis
What is the formula for iron (III) oxide?
FeO correct Fe2O3 Fe2O2 Fe3O2
Using the VSEPR theory, which of the following molecules exhibit tetrahedral molecular geometry. (Select all that apply.)
H2O HCl CO2 correct CH4 correct SiF4 PCl5
Magnesium reacts vigorously with hydrochloric acid to produce magnesium chloride and which other product?
HMg HCl correct H2 MgH
The formula for sodium oxide is Na2O. What is the formula of potassium sulfide? Enter the formula in the form of the element symbol followed by the subscript such as MgCl2 or N2O5.
K2S3 correct K2S K2S2 KS KS2
Indicate whether the following inorganic compounds are soluble or insoluble in water.
KNO3 soluble CuS insoluble AgCl insoluble BaSO4 insoluble Pb(NO3)2 soluble NaOH soluble
What is the formula for lithium oxide?
LiO2 correct Li2O LiO Li2O2
2 Li + 2 H2O 2 X + H2 Which compound does the X represent? (Type your answer using the format CO2 for CO2.)
LiOH
What is the formula for magnesium phosphate?
MgPO4 correct Mg3(PO4)2 Mg3PO4 Mg2(PO4)3
In order to satisfy the octet rule, which of the following molecular formulae must contain a double bond? (Select all that apply.)
N2H4 C2H6 correct O2 BF3
What is the formula for dinitrogen pentoxide?
N2O10 NO5 N5O2 correct N2O5
Which molecule is nonpolar?
NH3 CO correct CO2 H2O
Which 5.0 milliliter sample of NH3 will take the shape of and completely fill a closed 100.0 milliliter container?
NH3(aq) NH3(l) correct NH3(g) NH3(s)
For the following combination of reactants, enter the formulae of the products in the space provided and give their states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) NaI(aq) + Cl2(g) --->
NaI(aq) + Cl2(g) ---> I2(s),NaCl(aq) -or- NaCl(aq),I2(s) What type of reaction is this? combustion decomposition correct single replacement double replacement synthesis
Which of the following compounds contains 57.5% sodium by mass?
NaOH NaHCO3 NaI NaSO3
Which of the following molecules are polar? (Select all that apply.)
PCl5 correct H2O CH4 CO2 SiF4 correct HCl
For the following combination of reactants, enter the formulae of the products in the space provided and give their physical states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) Pb(NO3)4(aq) + K2CO3(aq)--->
Pb(NO3)4(aq) + K2CO3(aq)---> Pb(CO3)2(s), KNO3(aq) -or- KNO3(aq), Pb(CO3)2(s) What type of reaction is this? combustion decomposition single replacement correct double replacement synthesis
Which of these elements is the best conductor of electricity?
S correct Ni N Br
Which molecule has the least polar bonds?
SO2 correct NO2 CO2 P2O5
What must happen to an electron in an atom in order for light energy to be given off?
The electron must jump from a lower energy level to a higher one. correct The electron must drop from a higher energy level to a lower one. The electron is captured by a proton and becomes a neutron. The electron must move from an s orbital to a p orbital.
An unknown compound analyzes to be 24.7% C, 2.1% H, and 73.2% Cl. A 3.557 g sample of the gas occupies 750. mL at 837 mm Hg and 0.0°C. Type your answers using the format CH4 for CH4. Enter the elements in the order given.
What is the empirical formula of the compound? CHCl What is the molecular formula of the compound? C2H2Cl2
An unknown compound containing C, Cl, and F analyzes to be 11.79% C and 69.57% Cl. A 0.107 g sample of the gas occupies 458 mL at 21.3 mm Hg and 25.0°C. Type your answers using the format CH4 for CH4. Enter the elements in the order given.
What is the empirical formula of the compound? CCl2F What is the molecular formula of the compound? C2Cl4F2
For the following combination of reactants, enter the formulae of the products in the space provided and give their states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) ZnCO3(s) + heat--->
ZnCO3(s) + heat---> CO2(g),ZnO(s) -or- ZnO(s),CO2(g) What type of reaction is this? combustion correct decomposition single replacement double replacement synthesis
How many unpaired electrons are present in each of the following elements? Enter your answers as numerals.
a) Al 1 b) V 3 c) K 1 d) As 3 e) Ba 0
For each of the following pairs, indicate which atom or ion has the smaller ionzation energy.
a) Na or F Na b) Ca^2+ or Ca Ca c) Ne or Cl Cl d) N or F- N e) Cl- or I- I- -or- I f) Ca or Zn Ca g) Al or S Al
Determine the atom in each pair that has the larger ionization energy.
a) Na or K Na b) Cl or F F c) H or He He d) Ca or Br Br e) S or Al S
Determine the atom in each pair that has the smaller ionization energy.
a) Na or Mg Na b) P or Cl P c) Ne or He Ne d) Ca or Ba Ba e) B or Al Al
How many unpaired electrons are present in each of the following elements? Enter your answers as numerals.
a) Pb 2 b) Rn 0 c) Au 1 d) Hg 0 e) Bi 3
The number of neutrons in the nucleus of an atom can be determined by
adding the mass number of the atomic mass subtracting the mass number from the atomic number adding the atomic number to the mass number correct subtracting the atomic number from the mass number
Nitrogen and bromine are
alkaline earth metals transition metals metalloids correct nonmetals alkali metals
A cation is formed when
an atom gains electrons. an atom gains protons. correct an atom loses electrons. an atom loses protons.
An anion is a negative ion formed as
an atom gains protons. an atom loses electrons. correct an atom gains electrons. an atom loses protons.
Which of the following atoms has the greatest tendency to attract electrons?
barium boron beryllium correct bromine
Cr(s) + Cl2(g) ---> CrCl3(s) SiO2(s) + C(s) ---> Si(s) + CO(g) Fe(s) + H2O(g) ---> Fe3O4(s) + H2(g)
combustion correct single replacement double replacement synthesis
Referring to the tables and the figure below, identify liquid 2. Solids Density (g/mL) paraffin 0.95 rubber 8.6 cork 0.32 plastic 0.87 Liquids Density (g/mL) corn oil 0.92 water 1.0 mercury 13.6 ethanol 0.79
corn oil
The diagram below represents a portion of a 100 milliliter graduated cylinder. What is the reading of the meniscus?
correct 35.0 mL 36.0 mL 44.0 mL 45.0 mL
Many advertising signs depend on the production of light emissions from gas-filled glass tubes that are subjected to a high-voltage source. When light emissions are passed through a spectroscope, bright-line spectra are produced. (Select all that apply.)
correct A B C correct D
What is the formula for aluminum nitrate?
correct Al(NO3)3 Al3NO Al(NO2)3 AlN3
A compound has a gram formula mass of 56 grams per mole. What is the molecular formula for this compound?
correct C4H8 C2H4 C3H6 CH2
When a mass of vanillin, the main flavoring in vanilla,was completely combusted in oxygen, the mole ratios of the carbon, hydrogen, and oxygen in the products were 0.889 mol C, 0.890 mol H, and 0.333 mol O. What is the empirical formula of vanillin?
correct C8H8O3 C5H5O2 C3H3O C8H8O6
What is the formula for carbon tetrachloride?
correct CCl4 C4Cl4 CCl C4Cl
Which compound contains ionic bonds?
correct CaO NO2 NO CO2
What is the correct formula for iron (III) phosphate?
correct FePO4 Fe3(PO4)2 FeP Fe3P2
What is the formula for potassium carbonate?
correct K2CO3 P2CO3 KCO3 P(CO3)2
What is the empirical formula of a compound with the molecular formula N2O4?
correct NO2 NO N2O N2O3
Which formula represents an ionic compound?
correct NaCl N2O H2O HCl
Which of the following represents the correct Lewis structural model for CO2?
correct O=C=O C=O=C C-O-O O-C-O
Which species does not have a noble gas electron configuration?
correct S Mg2+ Na+ Ar
Which elements are chemically similar to each other?
correct Sulfur Iron Aluminum Carbon Iodine correct Oxygen
Which of the following are characteristics of most ionic solids? (Select all that apply.)
correct They are brittle. They conduct electricity in the solid state. correct They tend to be crystalline solids. correct They conduct electricity when dissolved in water. correct They conduct electricity in the molten state. They have low melting points.
Which of the following are properties of solids? (Select all that apply.)
correct definite volume high compressibility indefinite shape low density correct definite shape indefinite volume correct low compressibility correct high density
Which of the following are properties of ionic compounds? (Select all that apply.)
correct electrical conductor as a liquid soluble in nonpolar solvents correct high melting point very soft correct electrical conductor in solution nonconductor of electricity in all physical states correct nonvolatile correct nonconductor of electricity as a solid correct soluble in polar solvents volatile low melting point correct brittle
Metals are generally
correct good heat conductors liquids are room temperature correct malleable poor electrical conductors correct shiny gases at room temperature
Which of the following are properties of gases? (Select all that apply.)
correct indefinite volume correct indefinite shape correct low density low compressibility definite volume high density correct high compressibility definite shape
The energy needed to remove an electron from an atom is called what?
correct ionization energy electron affinity electronegativity activation energy
Which of the following are properties of liquids? (Select all that apply.)
correct low compressibility correct indefinite shape indefinite volume definite shape correct definite volume low density correct high density high compressibility
Boron and silicon are
correct metalloids transition metals alkaline earth metals metals alkali metals nonmetals
BaCl2(aq) + 2 NaOH(aq) BaOH2(s) + 2 NaCl(aq) What is missing in the equation above? (Select all that apply.)
correct parenthesis in a product subscript in a reactant coefficient in a product subscript in a product coefficient in a reactant
Which of the following are properties of a nonmetal? (Select all that apply.)
correct soft or brittle correct poor heat conductor correct poor electrical conductor malleable good heat conductor good electrical conductor
The electronegativity of the main group elements generally increases within a group on the periodic table as one moves
correct up the group for both metals and nonmetals up the group for metals and down the group for nonmetals down the group for both metals and nonmetals down the group for metals and up the group for nonmetals
Which of the following are properties of molecular compounds? (Select all that apply.)
correct volatile high boiling point very hard correct nonconductor of electricity as a solid correct nonconductor of electricty as a liquid electrical conductor in solution correct low boiling point nonvolatile correct soft
Which intermolecular forces explain why water is a liquid at room temperature? (Select all that apply.)
covalent bonding correct hydrogen bonding Van der Waal forces London forces dipole-dipole attractions ionic bonding
As the atomic number increases in a group (family) on the Periodic Table, electronegativity tends to______.
decrease
All the isotopes of a given atom have
different mass numbers and different atomic numbers the same mass number but different atomic numbers the same mass number and the same atomic numbers correct different mass numbers but the same atomic number
Compared to the nonmetals in Period 2, the metals in Period 2 generally have larger
electronegativities correct atomic radii atomic numbers ionization energies
Copper and silver are members of the
halogens alkali metals correct transition metals noble gases alkaline earth metals
Metals tend to have
high ionization energies because they gain electrons easily. correct low ionization energies because they lose electrons easily. low ionization energies because they gain electrons easily. high ionization energies because they lose electrons easily.
The most active nonmetals have the __________.
highest electronegativities.
In Period 3, from left to right in order, each successive element will
increase in metallic character correct increase in number of protons decrease in atomic mass decrease in electronegativity
Atomic radii tend to _____ left to right on the Periodic Table due to _____.
increase, decreased nuclear charge increase, increased nuclear charge decrease, decreased nuclear charge correct decrease, increased nuclear charge
What is the bond between Br atoms in a Br2 molecule?
ionic and is formed by the sharing of two valence electrons ionic and is formed by the transfer of two valence electrons correct covalent and is formed by the sharing of two valence electrons covalent and is formed by the transfer of two valence electrons
For the following combination of reactants, enter the formulae of the reactants in the order given in the original equation. Include the physical states of the reactants. For single and double replacement reactions, if the reactants are water soluble enter their physical states as (aq). If the reactants are not water soluble enter their physical states as (s). Enter the formulae of the products in the space provided and give their physical states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) lithium + nitrogen --->
lithium + nitrogen Li(s)+ N2(g) ---> Li3N(s) What type of reaction is this? combustion decomposition single replacement double replacement correct synthesis
The modern model of the atom shows that electrons are
located in a solid sphere covering the nucleus orbiting the nucleus in fixed paths correct found in regions called orbitals combined with neutrons in the nucleus
Metals tend to have __________.
low electronegativies.
What are two properties of most nonmetals?
low ionization energy and good electrical conductivity correct high ionization energy and poor electrical conductivity high ionization energy and good electrical conductivity low ionization energy and poor electrical conductivity
Which element is a noble gas?
manganese chlorine correct krypton antimony
Subatomic particles can usually pass undeflected through an atom because the volume of an atom is composed of
neutrons protons largely empty space an unchanged nucleus
As an electron goes from a higher energy level to a lower energy level in an atom, will energy be given off or absorbed?
not enough information to decide absorbed correct given off
Ionization energy tends to _____ from left to right across the periodic table.
not follow a pattern decrease correct increase stay the same
On the present Periodic Table of the Elements, the elements are arranged according to increasing what?
number of oxidation states atomic mass number of neutrons correct atomic number
Which of the following are properties of a metal? (Select all that apply.)
poor heat conductor correct good heat conductor correct good electrical conductor correct shiny brittle poor electrical conductor soluble in a polar solvent correct malleable
Compared to the radius of a chlorine atom, the radius of a chloride ion is
smaller because chlorine loses an electron smaller because chlorine gains an electron larger because chlorine loses an electron correct larger because chlorine gains an electron
For the following combination of reactants, enter the formulae of the reactants in the order given in the original equation. Include the physical states of the reactants. For single and double replacement reactions, if the reactants are water soluble enter their physical states as (aq). If the reactants are not water soluble enter their physical states as (s). Enter the formulae of the products in the space provided and give their physical states. (Separate multiple products with a comma ",". Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none".) sodium + water--->
sodium + water Na(s) + H2O(l) ---> NaOH(aq), H2(g) -or- H2(g), NaOH(aq) What type of reaction is this? combustion decomposition correct single replacement double replacement synthesis
A physical state composed of particles that vibrate in a fixed position is a
solution correct solid gas liquid
An electron has its lowest potential energy when the electron is which state?
the excited state correct the ground state the quantum state the neutral state