Questions and answers by

Morgan

Questions (558)

A 2.75 kg block of ice is heated until it completely melts. It is then heated again until it completely changes to water vapor.
1. 1 answer
2. 1,314 views
How can the atomic orbital be described in the quantum mechanical wave model of the orbitals?A. A collection of balloons B. A
1. 5 answers
2. 1,703 views
Core electrons shield what from the pull of the nucleus?A. Valence electrons B. Neutrons C. Protons I think the answer is a
1. 1 answer
2. 1,018 views
Which of the following elements can be detected by XPS?A. Hydrogen and lithium B. Boron and helium C. Lithium and boron I think
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2. 1,667 views
Nuclear magnetic resonance spectroscopy can be used to study which type of atoms?A. 16O B. 1H C. 2He
1. 4 answers
2. 1,418 views
Which of the following are excited in ultraviolet photoelectron spectroscopy?A. Valence electrons B. Core electrons C. X-rays
1. 2 answers
2. 2,113 views
How is a spectrum obtained in NMR spectroscopy?A. Low-frequency radio waves bombard the atom and cause nuclei in a low spin
1. 5 answers
2. 2,120 views
3. One problem the researchers faced was an uncertainty about whether the signals observed in certain mass spectrometry data
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2. 1,491 views
3. Is determining the excess reactant and limiting reactant an important part of a synthesis reaction? Is it an important part
1. 1 answer
2. 682 views
Suppose you designed an experiment in which you burned a known quantity of magnesium in air. You used the product to determine
1. 3 answers
2. 919 views
What is the form in which phosphorus exists in plant food and what ion could you use to precipitate the phosphorus.
1. 1 answer
2. 446 views
Use this article to answer questions about mass spectrometry and how it was used to identify lead isotopes in the air around
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2. 2,596 views
1. Why can’t gravimetric analysis be used to determine the concentration of sodium nitrate (NaNO) in a solution?2. Why is it
1. 2 answers
2. 2,324 views
A. What is the standard potential, in volts, of a galvanic cell made of Ce4+ and Cu2+, given the standard reduction potentials
1. 1 answer
2. 3,233 views
Identify the Oxidation and reduction half reaction in 2 KMNO4 + 10 FeSO4 + 8 H2SO4 -> K2SO4 + 2 MNSO4 + 5 Fe2(SO4)3 + 8 H2OWrite
1. 2 answers
2. 1,089 views
*Dickinson looking timidly too fearful to look up at this man questioning her about her seclusion*Please reword this for me.
1. 1 answer
2. 369 views
write 2-3 sentences describing and identifying the type of chemical reaction that occurs when Fe^2+ reacts with potassium
1. 1 answer
2. 1,072 views
identify the type of reaction that occurs between potassium carbonate and nitric acid
1. 1 answer
2. 1,776 views
This is a longer assignment. I want you to confirm my first two answers and help me figure out the last.3 Cu (s) + 8 HNO3 (aq)
1. 5 answers
2. 1,976 views
How might one challenge the idea that the United States was wiser after the Civil War?
1. 1 answer
2. 523 views
Which of the following elements can be detected by XPS?A. Hydrogen and lithium B. Boron and helium C. Lithium and boron
1. 1 answer
2. 890 views
Nuclear magnetic resonance spectroscopy can be used to study which type of atoms?A. 16O B. 1H C. 2He
1. 0 answers
2. 432 views
Which of the following are excited in ultraviolet photoelectron spectroscopy?A. Valence electrons B. Core electrons C. X-rays
1. 1 answer
2. 714 views
Brass is commonly used to make musical instruments because it is easily malleable and has excellent acoustic properties. It
1. 2 answers
2. 1,127 views
A. Ionic solidB. Molecular solid C. Covalent solid D. Graphic solid Which of this solids is soluble in water, conductive in
1. 1 answer
2. 759 views
Which of the following affects how strongly anions and cations are attracted to each other in a solid?A. The nucleus B. Empty
1. 2 answers
2. 2,617 views
The oscillation of electrons in an antenna is an example of which type of radiation/waves/rays?A. Radio waves B. Infrared rays
1. 3 answers
2. 1,124 views
Why are metals malleable?A. Because they reflect incoming photons B. Because they are made of atoms that have tightly held
1. 1 answer
2. 1,066 views
Which of the following is not true about molecular orbital theory?A. The bonding molecular orbital is filled before the
1. 1 answer
2. 3,506 views
The oscillation of electrons in an antenna is an example of which type of radiation/waves/rays?A. Radio waves B. Infrared rays
1. 2 answers
2. 1,761 views
Which of the following spectroscopies is/are suitable for studying materials on surfaces?A. IR and UV/V B. UV/V C. NMR D. XPS
1. 2 answers
2. 2,038 views
Which of the following is an example of sp3d2 hybridization?A. C2H6 B. IF7 C. PCl5 D. SF6
1. 2 answers
2. 2,683 views
Which statement best describes what must occur for two atoms to combine to form a chemical bond?A. The electrons of one nucleus
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2. 3,962 views
What is an ionic solid?A. One positive ion and one negative ion bonded to form a solid B. Many nonmetal atoms bonded together to
1. 1 answer
2. 789 views
In the Bohr model, which is the lowest energy state available for an electron?A. nth B. excited state C. first state D. ground
1. 1 answer
2. 1,271 views
Which electron would have the highest ionization energy for an oxygen atom?A. 2nd B. 1st C. 5th D. 6th If it is the highest I
1. 2 answers
2. 2,370 views
A. Orbital shapeB. Orientation in the orbital C. Main energy level D. Electron spin
1. 1 answer
2. 485 views
What is an ionic solid?A. One positive ion and one negative ion bonded to form a solid B. Many nonmetal atoms bonded together to
1. 1 answer
2. 478 views
For an atom of sulfur, which electron would require the least amount of energy to remove from the atom?A. 3s2 B. 1s1 C. 3p1 D.
1. 2 answers
2. 2,361 views
Which of the following is an example of quantization?A. The amount of time spent in a classroom B. The number of students in a
1. 3 answers
2. 2,171 views
Which of the following is an example of quantization?A. The amount of time spent in a classroom B. The number of students in a
1. 1 answer
2. 709 views
Marie, a resident of Metropolis, pays Metropolis an annual tax of $46 plus 2.4% of her annual income. If Marie paid $1,558 in
1. 1 answer
2. 487 views
Red light has a wavelength of 700 nm and a frequency of 4.3 x 1014 s-1. What is the energy of a single photon of red light?A.
1. 3 answers
2. 1,929 views
In which unit is the wavelength of an electromagnetic wave commonly measured?A. J B. nm C. s–1 D. kg All most positive it is b
1. 1 answer
2. 600 views
I just wanted to tell you that all my tests are supervised by a teacher. My questions are part of practice tests and review
1. 1 answer
2. 513 views
What does the photoelectric effect show about the connection between light and electrons?A. Light can remove electrons from
1. 2 answers
2. 1,944 views
A sodium atom when excited gives off two very specific wavelengths of visible light. What does this tell us about sodium?A.
1. 8 answers
2. 3,197 views
What is the difference between the ionization energy of inner-shell electrons and the ionization energy of outer-shell
1. 1 answer
2. 1,852 views
Which of the following is an example of quantization?A. The amount of time spent in a classroom B. The number of students in a
1. 3 answers
2. 5,821 views
Which statement describes the principal quantum number (n)?A. The quantum number that indicates the subshell occupied by an
1. 5 answers
2. 3,472 views
What does the fact that a blackbody can absorb light only in specific-sized "packets" say about light?A. It has no mass. B. It
1. 1 answer
2. 2,097 views
All electromagnetic energy (light), including gamma rays through radio waves, has what in common?A. Speed B. Wavelength C.
1. 2 answers
2. 2,205 views
What does electron affinity depend on?A. Both the effective nuclear charge and the number of shells in the atom containing
1. 0 answers
2. 942 views
Core electrons shield what from the pull of the nucleus?A. Identical electrons B. Valence electrons C. Neutrons D. Protons I was
1. 1 answer
2. 905 views
I am doing a lab and broke my glass beaker. Is it of to put 0.1 M hydrochloric acid in a plastic beaker?
1. 1 answer
2. 518 views
The ?H of the reaction below is -575.13 kJ. Is this reaction spontaneous?2ZnS + 3O2 + C ? 2SO2 + 2Zn + CO2 A. It is not because
1. 2 answers
2. 2,039 views
When 3.2 g of ammonium chloride is dissolved in 75 g of water, the temperature of the solution decreases from 22.8°C to
1. 10 answers
2. 2,988 views
When 3.2 g of ammonium chloride is dissolved in 75 g of water, the temperature of the solution decreases from 22.8°C to
1. 4 answers
2. 1,880 views
A sample of nickel is heated to 95.0°C and placed in a coffee-cup calorimeter. If the 50.0 g of water in the calorimeter is
1. 3 answers
2. 2,106 views
A sample of nickel is heated to 95.0°C and placed in a coffee-cup calorimeter. If the 50.0 g of water in the calorimeter is
1. 1 answer
2. 1,857 views
What is the entropy change associated with the chemical reaction that occurs when iron oxide is converted to its metal form?Fe2O
1. 5 answers
2. 3,628 views
The enthalpy of formation of C2H5OH is -238.7 kJ/mol. What information does this reveal about the bonds in the molecule?A. Bond
1. 1 answer
2. 3,611 views
Compute Mary's estimated tax payment for the first quarter. She is self-employed and she expects to earn $61,440 this year. Her
1. 0 answers
2. 504 views
Juan oye _____ su perro Spot.Would I use a personal a in the blank or leave it as it is.
1. 5 answers
2. 2,934 views
I just need an explanation of to solve the following:f(x)= ln (x^3 + 5)+ 6x
1. 1 answer
2. 468 views
If ammonia is manufactured at 356 K, is the reaction spontaneous, given that the enthalpy and entropy change for the reaction
1. 3 answers
2. 2,215 views
The ΔH of the reaction below is -575.13 kJ. Is this reaction spontaneous?2ZnS + 3O2 + C → 2SO2 + 2Zn + CO2 A. It is not
1. 1 answer
2. 722 views
At temperatures above 0°C, what is the sign of the change in free energy for the conversion of liquid water to ice?A. Positive
1. 1 answer
2. 557 views
During the 1920s, Women assumed new roles. List these roles; then choose one and describe in 5 – 10 sentences the impact of
1. 1 answer
2. 542 views
Why is it important in gravimetric analysis to add an excess amount of precipitating ions to a solution containing an analyte
1. 2 answers
2. 1,097 views
why can't gravimetric analysis be used to determine the concentration of sodium nitrate (NaNO) in a solution?I think the answer
1. 1 answer
2. 2,065 views
When a ball is thrown vertically upwardinto the air with a velocity of 79 ft/sec its height, y(t), in feet after t seconds is
1. 1 answer
2. 797 views
What is Gibbs free energy?A. The energy lost as heat to the surrounding molecules B. The usable energy released or absorbed by a
1. 0 answers
2. 636 views
At temperatures above 0°C, what is the sign of the change in free energy for the conversion of liquid water to ice?A. Positive
1. 0 answers
2. 446 views
What is Gibbs free energy?A. The energy lost as heat to the surrounding molecules B. The usable energy released or absorbed by a
1. 3 answers
2. 863 views
If the ΔH for H2O(l) → H2O(s) is -6.01 kJ, then what is the ΔH for 2H2O(s) → 2H2O(l)?A. -12.02 kJ B. 6.01 kJ C. -6.01 kJ
1. 0 answers
2. 338 views
What will be the result of a reaction if its enthalpy change is positive, its entropy change is negative and Gibbs free energy
1. 1 answer
2. 581 views
The G value for formation of gaseous water at 298 K and 1 atm is -278 kJ/mol. What is the nature of the spontaneity of formation
1. 1 answer
2. 771 views
What is steel?A. It is a compound of iron and various other elements including carbon. B. It is an ionic substance made of iron
1. 2 answers
2. 697 views
Which of the following correctly describes the net energy change during a reaction?A. The net change in energy is negative for
1. 1 answer
2. 1,726 views
What is Gibbs free energy?A. The energy lost as heat to the surrounding molecules B. The usable energy released or absorbed by a
1. 0 answers
2. 636 views
Why is the process of examining enthalpies of a reaction helpful?A. It helps in determining how a reaction occurs spontaneously.
1. 1 answer
2. 1,101 views
In the roasting of zinc ore, the total enthalpy for the reactants is -412.0 kJ and the total enthalpy for the products is
1. 1 answer
2. 698 views
When is there a need to determine G?A. When H > 0 and S = 0 B. When H > 0 and S > 0 C. When H = 0 and S < 0 D. When H > 0 and S
1. 0 answers
2. 305 views
What is Gibbs free energy?A. The energy lost as heat to the surrounding molecules B. The usable energy released or absorbed by a
1. 2 answers
2. 1,235 views
What is Gibbs free energy?A. The energy lost as heat to the surrounding molecules B. The usable energy released or absorbed by a
1. 0 answers
2. 670 views
What is ΔH in the equation ΔG = ΔH - TΔS?A. The change in specific heat between the products and the reactants B. The change
1. 4 answers
2. 3,867 views
What would cause entropy to increase in a reaction?A. The products forming a more rigid structure B. The products forming an
1. 6 answers
2. 1,384 views
Which of the following processes would result in a negative entropy change?A. Leaves falling off a tree B. A deck of cards
1. 2 answers
2. 1,840 views
I have to answer these questions:5. Compare the viewpoints of the senators in the Versailles Treaty. 6. What was the final
1. 1 answer
2. 738 views
What does the second law of thermodynamics say about entropy?A. Only changes in entropy can be measured. B. The entropy in a
1. 2 answers
2. 1,126 views
What characteristic best describes the low entropy associated with solids?A. The atoms in a solid are mostly metals. B. The
1. 3 answers
2. 3,509 views
Which of the following would have the greatest entropy?A. Water placed in the refrigerator B. Water sitting out on the kitchen
1. 1 answer
2. 1,410 views
I have an assignment. It has two boxes to model the particles of the same gas at different temperature (18 and 45 degrees
1. 3 answers
2. 782 views
Which of the following chemical reactions is an example of an endothermic reaction?A. Making ice cubes from liquid water B.
1. 1 answer
2. 793 views
What is the purpose of a calorimeter?A. To determine the temperature of a chemical reaction B. To determine the energy changes
1. 2 answers
2. 677 views
In the reaction AgNO3(aq) + HCl(aq) AgCl(s) + HNO3(aq) + heat, when 0.70 mole of AgNO3 and 0.70 mole of HCl react, the
1. 1 answer
2. 1,881 views
Which of the following contains more thermal energy?A. Water at 100°C B. Ice at 0°C C. Water at 0°C D. Steam at 100°C I
1. 3 answers
2. 1,068 views
Which of the following phrases can describe an endothermic process?A. A system gives off energy as it cools down. B. Energy is
1. 2 answers
2. 1,765 views
Hf < 0 implies which of the following?A. The temperature decreases B. The temperature remains the same C. A bond-forming process
1. 2 answers
2. 1,181 views