mastering chem sg

NH4+ and PO43− Express your answer as a chemical formula.

(NH4)3PO4

Consider the following selected postulates of Dalton's atomic theory: (i) Each element is composed of extremely small particles called atoms. (ii) Atoms are indivisible. (iii) Atoms of a given element are identical. (iv) Atoms of different elements are different and have different properties. Which of the postulates is(are) no longer considered valid?

(ii) and (iii)

Given the data in the table below, ΔH°rxn for the reaction 4NH3 (g) + 5O2 (g) → 4NO (g) + 6H2O (l) is ________ kJ. Substance ΔH∘f(kJ/mol) H2O (l) -286 NO (g) 90 NO2 (g) 34 HNO3 (aq) -207 NH3 (g) -46

-1172

Given the data in the table below, ΔH°rxn for the reaction Ca(OH)2 + 2H3AsO4 → Ca(H2AsO4)2 + 2H2O is ________ kJ. Substance ΔH∘f(kJ/mol) Ca(OH)2 -986.6 H3AsO4 -900.4 Ca(H2AsO4)2 -2346.0 H2O -285.9

-130.4

Given the following reactions 2S (s) + 3O2 (g) → 2SO3 (g) ΔH = -790 kJ S (s) + O2 (g) → SO2(g) ΔH = -297 kJ the enthalpy of the reaction in which sulfur dioxide is oxidized to sulfur trioxide 2SO2 (g) + O2 (g) → 2SO3 (g) is ________ kJ.

-196

A balloon originally had a volume of 4.39 L at 44 °C and a pressure of 729 torr. The balloon must be cooled to ________ °C to reduce its volume to 3.78 L (at constant pressure).

0.0

A 0.325 L flask filled with gas at 0.950 atm and 19 °C contains ________ mol of gas.

0.0129

How many moles of pyridine (C5H5N) are contained in 3.13 g of pyridine

0.0396

The wavelength of light that has a frequency of 1.66 × 109 s-1 is ________ m

0.181

A mixture of Xe, Kr, and Ar has a total pressure of 7.15 atm. What is the mole fraction of Kr if the partial pressures of Xe and Ar are 1.45 atm and 2.10 atm, respectively.

0.503

Indicate the number of unpaired electrons for the following: [noble gas]ns2(n−1)d10np1 Express your answer as an integer.

1

Indicate the number of unpaired electrons for the following: [noble gas]ns2np5 Express your answer as an integer.

1

When the following equation is balanced, the coefficient of H2 is ________. K (s) + H2O (l) → KOH (aq) + H2 (g)

1

When the following equation is balanced, the coefficient of H3PO4 is ________. H3PO4 (aq) + NaOH (aq) → Na3PO4 (aq) + H2O (l)

1

1 mole of which of the following will contain the largest number of atoms?

1 mole of any element will contain the same number of atoms.

Which of the following is not a valid set of four quantum numbers? (n, l, ml , ms) 3, 1, -1, -1/2 2, 0, 0, +1/2 2, 1, 0, -1/2 1, 0, 0, +1/2 1, 1, 0, +1/2

1, 1, 0, +1/2

How many sulfur dioxide molecules are there in 1.80 mol of sulfur dioxide

1.08 × 1024

What is the maximum mass in grams of NH3 that can be produced by the reaction of 1.0 g of N2 with 3.0 g of H2 via the equation below? N2 (g) + H2 (g) → NH3 (g) (not balanced)

1.2

Molten gallium reacts with arsenic to form the semiconductor, gallium arsenide, GaAs, used in light emitting diodes and solar cells: Ga(l) + As(s) → GaAs(s) If 4.00 g of gallium is reacted with 5.50 g of arsenic how many grams of the excess reactant are left at the end of the reaction?

1.20 g As

A sample of aluminum metal absorbs 9.86 J of heat, upon which the temperature of the sample increases from 23.2 °C to 30.5 °C. Since the specific heat capacity of aluminum is 0.90 J/g-K, the mass of the sample is ________ g.

1.5

How many chlorine atoms are there in 12.2 g of CCl4

1.91×1023 atoms

A certain orbital of the hydrogen atom has n = 4 and l = 2. What are the possible values of ms for the orbital?

1/2, -1/2

A hydrogen atom orbital has n=5 and ml=−2 What are the possible values of ms for the orbital?

1/2, -1/2

Each d-subshell can accommodate a maximum of ________ electrons

10

There are ________ mol of carbon atoms in 5 mol of dimethylsulfoxide (C2H6SO).

10

The formula weight of Li2SO4 is ________ amu.

109.9

At a temperature of ________ °C, 0.444 mol of CO gas occupies 11.8 L at 923 torr.

119

A fixed amount of gas at 25.0 °C occupies a volume of 8.66 L when the pressure is 629 torr. Use Charles's law to calculate the volume (L) the gas will occupy when the temperature is increased to 155°C while maintaining the pressure at 629 torr.

12.4

Identify the group of elements that corresponds to the following generalized electron configuration: [noble gas]ns2(n−1)d10np1 Enter the group number corresponding to the electron configuration.

13

When 24 mol of methanol and 15 mol of oxygen combine in the combustion reaction, 2 CH3OH(g) + 3 O2(g) → 2 CO2(g) + 4 H2O(g) what is the excess reactant and how many moles of it remain at the end of the reaction?

14 mol CH3OH(g

Identify the group of elements that corresponds to the following generalized electron configuration: [noble gas]ns2np5 Enter the group number corresponding to the electron configuration.

17

Given the following reactions N2 (g) + 2O2 (g) → 2NO2 (g) ΔH = 66.4 kJ 2NO (g) + O2 (g) → 2NO2 (g) ΔH = -114.2 kJ the enthalpy of the reaction of the nitrogen to produce nitric oxide N2 (g) + O2 (g) → 2NO (g) is ________ kJ.

180.6

Indicate the number of unpaired electrons for the following: [noble gas]ns2(n−1)d2 Express your answer as an integer

2

A sample of an ionic compound containing iron and chlorine is analyzed and found to have a molar mass of 126.8 g/mol. What is the charge of the iron in this compound?

2+

Which of the following is a valid set of four quantum numbers? (n, l, ml , ms) 1, 0, 1, +1/2 1, 1, 0, -1/2 2, 2, 1, -1/2 2, 1, +2, +1/2 2, 1, 0, +1/2

2, 1, 0, +1/2

When the following equation is balanced, the coefficients are ________. C6H14+O2→CO2+H2O

2, 19, 12, 14

When the following equation is balanced, the coefficients are ________. C8H18 + O2 → CO2 + H2O

2, 25, 16, 18

When the following equation is balanced, the coefficients are ________. Al(NO3)3 + Na2S → Al2S3 + NaNO3

2, 3, 1, 6

A certain orbital of the hydrogen atom has n = 4 and l = 2. What are the possible values of ml for this orbital?

2,1,0,-1,-2

A hydrogen atom orbital has n=5 and ml=−2 What are the possible values of l for this orbital?

2,3,4

10.0 grams of argon and 20.0 grams of neon are placed in a 1170.0 ml container at 27.0 °C. The partial pressure of neon is ________ atm

20.9

What is the atomic number of the element chromium?

24

A sample of gas (24.2 g) initially at 6.00 atm was compressed from 8.00 L to 2.00 L at constant temperature. After the compression, the gas pressure was ________ atm.

24.0

If 50.75 g of a gas occupies 10.0 L at STP, 129.3 g of the gas will occupy ________ L at STP.

25.5

The wavelength of light emitted from a traffic light having a frequency of 1.18×1014 Hz is ________ nm.

2540

A certain mass of carbon reacts with 128 g of oxygen to form carbon monoxide. ________ grams of oxygen would react with that same mass of carbon to form carbon dioxide, according to the law of multiple proportions.

256

Calculate the percentage by mass of oxygen in Pb(NO3)2.

29.0

What is the mass % of oxygen in lead (II) nitrate (Pb(NO3)2) rounded to three significant figures?

29.0

The formula weight of potassium dichromate (K2Cr2O7) is ________ amu

294.18

Which of the subshells below do not exist due to the constraints upon the angular momentum quantum number? 2p 2s 2d all of the above

2d

Which one of the following is not a valid value for the magnetic quantum number of an electron in a 5d subshell? 1 2 3 -1 0

3

Electromagnetic radiation travels through vacuum at a speed of ________ m/s

3.00 × 108

The wavelength of a photon that has an energy of 6.33 × 10-18 J is ________ m.

3.10 × 10-8

Electromagnetic radiation with a wavelength of 575 nm appears as yellow light to the human eye. The energy of one photon of this light is 3.46 × 10-19 J. Thus, a laser that emits 1.3 ×10-2 J of energy in a pulse of light at this wavelength produces ________ photons in each pulse.

3.8 ×1016

When the electron in a hydrogen atom moves from n = 8 to n = 2, light with a wavelength of ________ nm is emitted

389

Identify the group of elements that corresponds to the following generalized electron configuration: [noble gas]ns2(n−1)d2 Enter the group number corresponding to the electron configuration.

4

When the following equation is balanced, the coefficients are ________. NH3 (g) + O2 (g) → NO2 (g) + H2O (g)

4, 7, 4, 6

CO (5.00 g) and CO2 (5.00 g) were placed in a 750.0 mL container at 50.0 °C. The partial pressure of CO2 in the container was ________ atm

4.02

The wavelength of an electron whose velocity is 1.7 × 104 m/s and whose mass is 9.1 × 10-28 g is ________ m.

4.3 × 10-8

Electromagnetic radiation with a wavelength of 665 nm appears as orange light to the human eye. The frequency of this light is ________ s-1.

4.51 × 1014

f 73.5 grams of FeS2 is allowed to react with 44 grams of O2 according to the following equation, how many grams of Fe2O3 are produced? FeS2 + O2 → Fe2O3 + SO2

40.0

The formula weight of Pb(ClO4)2 is ________ amu

405.9

When the following equation is balanced, the coefficient of O2 is ________. C2H4O (g) + O2 (g) → CO2 (g) + H2O (g)

5

There are ________ sulfur atoms in 25 molecules of C4H4S2

50

Determine which of the following samples contains the fewest sodium atoms?

50 g sodium chloride

Each p-subshell can accommodate a maximum of ________ electrons

6

Indicate the number of unpaired electrons for the following: [noble gas]ns2(n−2)f6 Express your answer as an integer.

6

SO2 (5.00 g) and CO2 (5.00 g) were placed in a 750.0 mL container at 50.0 °C. The total pressure in the container was ________ atm.

6.78

Based on the structure of the periodic table, which becomes occupied first, the 6 s orbital or the 5d orbitals?

6s

What is the mass % of hydrogen in dimethylsulfoxide (C2H6SO) rounded to three significant figures?

7.74

A sample of calcium carbonate [CaCO3 (s)] absorbs 53.7 J of heat, upon which the temperature of the sample increases from 19.5 °C to 27.8 °C. If the specific heat of calcium carbonate is 0.82 J/g-K, what is the mass (in grams) of the sample?

7.9 g

A pressure of 1.00 atm is the same as a pressure of ________ of mm Hg.

760

How many grams of hydrogen are in 69 g of CH4O?

8.7

A 4.50-g sample of copper metal at 25.0 °C is heated by the addition of 96.0 J of energy. The final temperature of the copper is ________ °C. The specific heat capacity of copper is 0.38 J/g-K.

81.1

A fixed amount of gas at 25.0 °C occupies a volume of 10.0 L when the pressure is 667 torr. Use Boyle's law to calculate the pressure (torr) when the volume is reduced to 8.13 L at a constant temperature of 25.0 °C.

820

A sample of gas (1.3 mol) occupies ________ L at 22 °C and 3.5 atm.

9.0

Calculate the percentage by mass of nitrogen in PtCl2(NH3)2.

9.34

If 3.21 mol of a gas occupies 56.2 L at 44 °C and 793 torr, 5.36 mol of this gas occupies ________ L under these conditions.

93.8

If 3.00 g of titanium metal is reacted with 6.00 g of chlorine gas, Cl2, to form 7.7 g of titanium (IV) chloride in a combination reaction, what is the percent yield of the product?

96%

The specific heat capacity of liquid water is 4.18 J/g-K. How many joules of heat are needed to raise the temperature of 6.00 g of water from 36.0 °C to 75.0 °C?

978 J

All of the orbitals in a given subshell have the same value as the ________ quantum number. A) principal B) angular momentum C) magnetic A and B B and C

A and B

A compound whose empirical formula is XF3 consists of 65 % F by mass. What is the atomic mass of X? Express your answer using two significant figures

AMX = 31g/mol

Which of the following is soluble in water at 25∘C?

AgNO3

Which of the following correctly represents the third ionization of aluminum? Al2+ (g) → Al3+ (g) + e- Al2+ (g) + e- → Al+ (g) Al2+ (g) + e- → Al3+ (g) Al (g) → Al+ (g) + e- Al2- (g) + e- → Al3- (g)

Al2+ (g) → Al3+ (g) + e-

Of the choices below, which gives the order for first ionization energies? Cl > S > Al > Si > Ar Cl > S > Al > Ar > Si S > Si > Cl > Al > Ar Ar > Cl > S > Si > Al Al > Si > S > Cl > Ar

Ar > Cl > S > Si > Al

The first ionization energy and the electron affinity of Ar are both positive values. What is the significance of the positive value in each case?

Ar is a Nobel gas, therefore it has a stable electron configuration. This causes the element to resist chemical change. Positive values for ionization energy and electron affinity means that energy is required to either remove or add electrons. Valance electrons in Ar experience the largest affinity of any element in the 3rd row of the periodic table. This results in a positive ionization energy. When an electron is added to Ar, the n=3 electrons become core electrons, this results in a large positive electron affinity.

[Ar]4s23d104p3 is the electron configuration of a(n) ________ atom.

As

Which one of the following is not one of the postulates of Dalton's atomic theory? Atoms are composed of protons, neutrons, and electrons. Atoms of an element are not changed into different types of atoms by chemical reactions: atoms are neither created nor destroyed in chemical reactions. All atoms of a given element are identical; the atoms of different elements are different and have different properties. Each element is composed of extremely small particles called atoms. Compounds are formed when atoms of more than one element combine; a given compound always has the same relative number and kind of atoms.

Atoms are composed of protons, neutrons, and electrons

What element has an atomic number of 56

Barium (Ba)

Identify the specific element that corresponds to each of the following electron configurations. 1s2 2s2

Be

Serotonin is a compound that conducts nerve impulses in the brain. It contains 68.2 mass percent C, 6.86 mass percent H, 15.9 mass percent N, and 9.08 mass percent O. Its molar mass is 176 g/mol. Determine its molecular formula. Express your answer as a chemical formula.

C10H12N2O

which hydrocarbon pair below has identical mass percentage of C C2H4 and C4H2 C2H4 and C3H4 C3H4 and C3H6 C2H4 and C3H6 none of the above

C2H4 and C3H6

A compound contains 40.0% C, 6.71% H, and 53.29% O by mass. The molecular weight of the compound is 60.05 amu. The molecular formula of this compound is ________.

C2H4O2

What is the empirical formula of a compound that is 39.3 % C, 8.3 % H, and 52.4 % O by mass?

C2H5O2

A compound that is composed of carbon, hydrogen, and oxygen contains 70.6% C, 5.9% H, and 23.5% O by mass. The molecular weight of the compound is 136 amu. What is the molecular formula?

C8H8O2

The element that has a valence configuration of 4s2 is _______

Ca

Ca2+ and ClO3− Express your answer as a chemical formula.

Ca(ClO3)2

Of the following atoms, which has the largest first ionization energy? Na Al Br Se Cl

Cl

Identify the specific element that corresponds to each of the following electron configurations. [Ar]4s1 3d5

Cr

The ground-state electron configuration of ________ is [Ar]4s13d5

Cr

Cr3+ and Br− Express your answer as a chemical formula.

CrBr3

Ag 328.1nm Fe 372.0nm Au 267.6nm K 404.7nm Ba 455.4nm Mg 285.2nm Ca 422.7nm Na 589.6nm Cu 324.8nm Ni 341.5nm When burned, a sample of an unknown substance is found to emit light of frequency 9.23×1014s−1. Which of these elements is probably in the sample?

Cu

Classify each of the following substances as an element, a compound, or a mixture. soil nitrogen monoxide, NOhydrogen peroxide, HOOH silver, Agneon, Ne

Element silver, Agneon, Ne Compound nitrogen monoxide, NOhydrogen peroxide, HOOH Mixture soil

Which scientist postulated the nuclear model of the atom?

Ernest Rutherford

Of the following elements, ________ has the most negative electron affinity. N Be F C O

F

Of the following, ΔH°f is not zero for _______ Cl2 (g) N2 (g) O2 (g) F2 (s) C (graphite)

F2 (s)

Fe3+ and O2− Express your answer as a chemical formula.

Fe2O3

The correct formula of iron (III) bromide is __

FeBr3

Hg22+ and CO32− Express your answer as a chemical formula.

Hg2CO3

Classify the following mixtures as homogeneous or heterogeneous. gravel sandwich salt water steel vodka

Homogenous mixture salt water steel vodka Heterogeneous mixture gravel sandwich

Classify the following as intensive or extensive properties of gold. lustrous yellow in color begins to melt at 1064 degrees Celsius has a density of 19.3 g/mL has a mass of 82.6 g has a volume of 4.28 mL

Intensive lustrous yellow in colorbegins to melt at 1064 degrees Celsius has a density of 19.3 g/mL Extensive has a mass of 82.6 g has a volume of 4.28 mL

Which of the following properties of a glass are physical properties? It has a mass of 5.4 g. It is transparent. Sodium fluoride and hydrogen fluoride are used in etching of glass. it is brittle

It has a mass of 5.4 g. It is transparent. It is brittle

If compound A has an equal number of oxygen and carbon atoms, what can we conclude about the composition of compound B? It has half as many oxygen than carbon atoms. It has twice as many oxygen than carbon atoms. It has an equal number of oxygen and carbon atoms.

It has twice as many oxygen than carbon atoms.

Which of the following properties of iron are chemical properties? It rusts in water. It has a mass of 112.23 g. It reacts with chlorine to form iron chloride. It is shiny

It reacts with chlorine to form iron chloride It rusts in water.

The units of heat capacity are ________.

J/K or J/°C

The element that has a valence configuration of 4s2 4p6 is ________

Kr

The ground-state electron configuration of the element ________ is [Kr]5s14d5.

Mo

The correct formula for molybdenum (IV) hypochlorite is

Mo(ClO)4

How do the molecules of a compound differ from the molecules of an element?

Molecules of a compound are composed of more than one type of atom, and molecules of an element are composed of only one type of atom.

A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be _______

N2O

Ag 328.1nm Fe 372.0nm Au 267.6nm K 404.7nm Ba 455.4nm Mg 285.2nm Ca 422.7nm Na 589.6nm Cu 324.8nm Ni 341.5nm Which element emits photons of lowest energy?

Na

One mole of ________ contains the smallest number of atoms. S8 NaCl C10H8 Na3PO4 Al2(SO4)3

NaCl

When aqueous solutions of ________ are mixed, a precipitate forms

NiBr2 and AgNO3

Identify the specific element that corresponds to each of the following electron configurations. 1s2 2s2 2p4

O

Which combination will produce a precipitate Pb(NO3)2 (aq) and HCl (aq) Cu(NO3)2 (aq) and KC2H3O2 (aq) NaOH (aq) and Sr(NO3)2 (aq) KOH (aq) and HNO3 (aq) AgC2H3O2 (aq) and HC2H3O2 (aq)

Pb(NO3)2 (aq) and HCl (aq)

What did the scientist Ernest Rutherford do in the early 1900s?

Postulated the nuclear model of the atom

What is the empirical formula of a compound that contains 27.0% S, 13.4% O, and 59.6% Cl by mass?

SOCl2

Of the following, ΔH°f is not zero for __ Ca (s) Si (s) Sc (g) Br2 (l) P4 (s, white)

Sc (g)

Of the following, ΔH°f is not zero for _____ Ca (s) Si (s) Sc (g) Br2 (l) P4 (s, white)

Sc (g)

Identify the elements that correspond to the following generalized electron configuration: [noble gas]ns2(n−2)f6 Enter the element symbol corresponding to the element indicated by the electron configuration. If there is more than one answer, separate them by a comma.

Sm,Pu

Identify the specific element that corresponds to each of the following electron configurations. [Kr]5s2 4d10 5p4

Te

Identify which of the following statements are true. Check all that apply. Oxygen has a larger first ionization energy than fluorine. The third ionization energy is the energy needed to ionize three electrons from a neutral atom. Ionization energies are always negative quantities. The second ionization energy of an atom is always greater than its first ionization energy.

The second ionization energy of an atom is always greater than its first ionization energy.

________ have the lowest first ionization energies of the groups listed. Noble gases Alkaline earth metals Halogens Transition elements Alkali metals

alkali metals

The elements in groups 1A, 6A, and 7A are called ________, respectively.

alkali metals, chalcogens, and halogens

Which one of the following orbitals can hold two electrons? 4dxy 3s 2px all of the above none of the above

all of the above

The name of the ionic compound NH4CN is

ammonium cyanide

The name of the ionic compound (NH4)3PO4 is

ammonium phosphate

The smallest building blocks of matter are called?

atoms

Which of the following is not part of the kinetic-molecular theory? The volume occupied by all of the gas molecules in a container is negligible compared to the volume of the container. Atoms are neither created nor destroyed by ordinary chemical reactions. Collisions between gas molecules do not result in the loss of energy. Attractive and repulsive forces between gas molecules are negligible. Gases consist of molecules in continuous, random motion.

atoms are neither created nor destroyed by ordinary chemical reactions.

Ag 328.1nm Fe 372.0nm Au 267.6nm K 404.7nm Ba 455.4nm Mg 285.2nm Ca 422.7nm Na 589.6nm Cu 324.8nm Ni 341.5nm Which element emits photons of highest energy

au

In a px orbital, the subscript x denotes the _____

axis along which the orbital is aligned

Ag 328.1nm Fe 372.0nm Au 267.6nm K 404.7nm Ba 455.4nm Mg 285.2nm Ca 422.7nm Na 589.6nm Cu 324.8nm Ni 341.5nm Determine which elements emit radiation in the visible part of the spectrum. Check all that apply.

ba ca k na

The kinetic-molecular theory predicts that pressure rises as the temperature of a gas increases because ________.

both the gas molecules collide more frequently with the wall and the gas molecules collide more energetically with the wall

Which atom has the largest number of neutrons? calcium-44 argon-38 silicon-30 sulfur-33 magnesium-26

calcium-44

The correct name for HClO3 is

chloric acid

In general, as you go across a period in the periodic table from left to right: (1) the atomic radius ________; (2) the electron affinity becomes ________ negative; and (3) the first ionization energy ________. decreases, increasingly, increases decreases, increasingly, decreases increases, increasingly, decreases

decreases, increasingly, increases

The energy of a photon of light is ________ proportional to its frequency and ________ proportional to its wavelength.

directly, inversely

Which separation method is better suited for separating a solution of salt and water into pure substances, filtration or distillation?

distillation

A sulfur oxide is 50.0% by mass sulfur. This molecular formula could be ___

either SO2 or S2O4

In the Bohr model of the atom, ________.

electron energies are quantized

Does the hydrogen atom "expand" or "contract" when an electron is excited from the n=1 state to the n=2 state?

expands

What state of matter has no fixed volume or shape

gas

Vertical columns of the periodic table are known as ________

groups

The ________ have the most negative electron affinities. halogens chalcogens transition metals alkali metals alkaline earth metals

halogens

A real gas will behave most like an ideal gas under conditions of ________

high temperature and low pressure

According to the classification of matter, a cup of milk viewed from the naked eye is considered to be what?

homogeneous mixture

The first ionization energies of the elements ________ as you go from left to right across a period of the periodic table, and ________ as you go from the bottom to the top of a group in the table.

increase, increase

A strong electrolyte is one that ________ completely in solution.

ionizes

What are the units of electron affinity?

kJ/mol

Compound A contains 3.222 g of oxygen per gram of carbon, whereas compound B contains 6.444 g of oxygen per gram of carbon. What chemical law do these data illustrate? law of multiple proportions law of constant composition law of conservation of mass

law of multiple proportions

Aqueous potassium chloride will react with which one of the following in an exchange (metathesis) reaction?

lead nitrate

Hydrogen sulfide is composed of two elements: hydrogen and sulfur. In an experiment, 6.900 g of hydrogen sulfide is fully decomposed into its elements. If 0.408 g of hydrogen is obtained in this experiment, how many grams of sulfur must be obtained? What fundamental law does this experiment demonstrate?

m = 6.492 g conservation of mass

Lithium is a ________ and magnesium is a ________

metal, metal

The symbol for the magnetic quantum number is ________.

ml

Which of the following is the best term to describe two or more atoms joined in a specific shape?

molecule

A weak electrolyte exists predominantly as ________ in solution.

molecules

Of the following transitions in the Bohr hydrogen atom, the ________ transition results in the emission of the lowest-energy photon. n = 1 → n = 4 n = 3 → n = 6 n = 6 → n = 1 n = 1 → n = 6 n = 6 → n = 3

n = 6 → n = 3

The correct name for HNO3 is

nitric acid

Horizontal rows of the periodic table are known as

periods

Which of these changes are physical and which are chemical? A goldsmith melts a nugget of gold and pulls it into a wire. Water vapor in the air forms frost. Plants make sugar from carbon dioxide and water.

physical changes A goldsmith melts a nugget of gold and pulls it into a wire. Water vapor in the air forms frost. chemical changes Plants make sugar from carbon dioxide and water.

Label each of the following as either a physical process or a chemical process. boiling a cup of water pulverizing an aspirin rusting of a metal can digesting a candy bar explosion of nitroglycerin

physical process boiling a cup of water pulverizing an aspirin chemical process rusting of a metal can digesting a candy bar explosion of nitroglycerin

Which of these characteristics are physical properties, and which are chemical properties? (a) The substance is a silvery white, lustrous metal. (b) The substance melts at 649 ∘C, (c) The substance boils at 1105 ∘C. (d) The density of the substance at 20 ∘C is 1.738 g/cm3. (e) The substance burns in air, producing an intense white light. (f) The substance reacts with chlorine to give a brittle white solid. (g) The substance can be pounded into thin sheets or drawn into wires. (h) The substance is a good conductor of electricity.

physical properties (a)(b)(c)(d)(g)(h) chemical properties (e)(f)

Of the following, the subatomic particle with a mass of 1 amu is the ________. molecule electron beta partic proton io

proton

The nucleus of an atom contains ________

protons and neutrons

-orbitals are spherically symmetrical.

s

1 mole of which of the following will have the largest mass

silver

The correct name for H2SO3 is ________

sulfurous acid

You are given a sample resembling gold. Which of the following properties could be used to help determine whether the sample is really gold? the volume of the sample the density of the sample the melting point of the sample

the density of the sample the melting point of the sample

According to the kinetic-molecular theory, molecules of different gases at the same temperature always have the same average kinetic energy. True False

true

Electron affinity measures how easily an atom gains an electron. True False

true

If a hydrogen atom electron jumps from the n=6 orbit to the n=2 orbit, energy is released. True False

true

The wavelength of radio waves can be longer than a football field. True False

true

In which form of water are the water molecules farthest apart?

water vapor

A baseball pitcher throws a fastball that moves at 95 miles per hour. Does that moving baseball generate matter waves? no yes If so, can we observe them? yes no

yes, no

From the enthalpies of reaction H2(g)+F2(g)→2HF(g)ΔH=−537kJ C(s)+2F2(g)→CF4(g)ΔH=−680kJ 2C(s)+2H2(g)→C2H4(g)ΔH=+52.3kJ calculate ΔH for the reaction of ethylene with F2: C2H4(g)+6F2(g)→2CF4(g)+4HF(g)

ΔHrxn = -2490kJ

Calculate the enthalpy change for the reaction P4O6(s)+2O2(g)→P4O10(s) given the following enthalpies of reaction: P4(s)+3O2(g)→P4O6(s)ΔH=−1640.1kJ P4(s)+5O2(g)→P4O10(s)ΔH=−2940.1kJ

ΔH∘rxn = -1300kJ