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Which particles are found in the nucleus of an argon atom?*
The diagram below represents a particle traveling through an electric field.
Which particle remains undeflected when passing through this electric field?*
The mass of an electron is*
Compared to the energy of an electron in the second shell of an atom of sulfur, the energy of an electron in the*
In the ground state, an atom of which element has seven valence electrons?*
Which information is sufficient to differentiate a sample of sodium from a sample of silver?*
Graphite and diamond are two forms of solid carbon at STP. These forms have*
As the first five elements in Group 14 are considered in order from top to bottom, there are changes in both the*
Which statement explains why NaBr is classifi ed as a compound?*
Which two terms represent types of chemical formulas?*
During all chemical reactions, charge, mass and energy are*
The degree of polarity of a covalent bond between two atoms is determined by calculating the difference in their*
Which substance can not be broken down by a chemical change?*
Which statement describes the components of a mixture?*
Table sugar can be separated from a mixture of table sugar and sand at STP by adding*
Which statement describes the particles of an ideal gas, based on the kinetic molecular theory?*
During which two processes does a substance release energy?*
Based on Table I, which compound dissolves in water by an exothermic process?*
At STP, which property of a molecular substance is determined by the arrangement of its molecules?*
Equilibrium can be reached by*
Which value is defined as the difference between the potential energy of the products and the potential energy of the reactants during a chemical change?*
The effect of a catalyst on a chemical reaction is to provide a new reaction pathway that results in a different*
Chemical systems in nature tend to undergo changes toward*
The atoms of which element bond to one another in chains, rings, and networks?*
What is the general formula for the homologous series that includes ethene?*
When an F atom becomes an F− ion, the F atom*
Which substance is an Arrhenius base?*
In which type of nuclear reaction do two light nuclei combine to produce a heavier nucleus?*
Using equal masses of reactants, which statement describes the relative amounts of energy released during a chemical reaction and a nuclear reaction?*
The ratio of the mass of U-238 to the mass of Pb-206 can be used to*
The bright-line spectra of four elements, G, J, L, and M, and a mixture of at least two of these elements is given below.
Which elements are present in the mixture?*
Which electron confi guration represents an atom of chlorine in an excited state?*
A student measures the mass and volume of a sample of aluminum at room temperature, and calculates the density of Al to be 2.85 grams per cubic centimeter. Based on Table S, what is the percent error for the student’s calculated density of Al?*
Magnesium and calcium have similar chemical properties because their atoms in the ground state have*
As the elements in Period 2 of the Periodic Table are considered in order from left to right, which property generally decreases?*
Given the balanced equation for the reaction of butane and oxygen:
2C4H10 + 13O2 → 8CO2 + 10H2O + energy
How many moles of carbon dioxide are produced when 5.0 moles of butane react completely?*
What is the percent composition by mass of nitrogen in the compound N2H4 (gram-formula mass = 32 g/mol)?*
Which ion in the ground state has the same electron confi guration as an atom of neon in the ground state?*
The molar masses and boiling points at standard pressure for four compounds are given in the table below.
Which compound has the strongest intermolecular forces?*
Which particle model diagram represents xenon at STP?
What is the amount of heat absorbed when the temperature of 75 grams of water increases from 20.°C to 35°C?*
Which sample of HCl(aq) reacts at the fastest rate with a 1.0-gram sample of iron fi lings?*
Given the equation representing a system at equilibrium:
N2O4(g) ⇌ 2NO2(g)
Which statement describes the concentration of the two gases in this system?*
PCl5(g) + energy ⇌ PCl3(g) + Cl2(g)
Which change will cause the equilibrium to shift to the right?*
Given the formula representing a molecule:
A chemical name for this compound is*
Given the formula of a compound:
This compound is classifi ed as an*
Which equation represents fermentation?*
Given the equation representing a reaction:
3CuCl2(aq) + 2Al(s) → 3Cu(s) + 2AlCl3(aq)
The oxidation number of copper changes from*
Given the equation representing a reversible reaction:
CH3COOH(aq) + H2O(ℓ) ⇌
CH3COO−(aq) + H3O+(aq)
According to one acid-base theory, the two H+ donors in the equation are*
Which nuclear equation represents a spontaneous decay?*
Draw a structural formula for methanal.*
Base your answers to questions 52 through 54 on the information below and on your knowledge of chemistry.
The atomic mass and natural abundance of the naturally occuring isotopes of hydrogen are shown in the table below.
The isotope H-2, also called deuterium, is usually represented by the symbol “D.” Heavy water forms when deuterium reacts with oxygen, producing molecules of D2O.
Explain, in terms of subatomic particles, why atoms of H-1, H-2, and H-3 are each electrically neutral.*
Determine the formula mass of heavy water, D2O.*
Based on Table N, identify the decay mode of tritium.*
Base your answers to questions 55 through 57 on the information below and on your knowledge of chemistry.
At 23°C, 85.0 grams of NaNO3(s) are dissolved in 100. grams of H2O(ℓ).
Convert the temperature of the NaNO3(s) to kelvins.*
Based on Table G, determine the additional mass of NaNO3(s) that must be dissolved to saturate the solution at 23°C.*
State what happens to the boiling point and freezing point of the solution when the solution is diluted with an additional 100. grams of H2O(ℓ).*
Base your answers to questions 58 through 61 on the information below and on your knowledge of chemistry.
A 200.-milliliter sample of CO2(g) is placed in a sealed, rigid cylinder with a movable piston at 296 K and 101.3 kPa.
State a change in temperature and a change in pressure of the CO2(g) that would cause it to behave more like an ideal gas.*
Determine the volume of the sample of CO2(g) if the temperature and pressure are changed to 336 K and 152.0 kPa.*
State, in terms of both the frequency and force of collisions, what would result from decreasing the temperature of the original sample of CO2(g), at constant volume.*
Compare the mass of the original 200.-milliliter sample of CO2(g) to the mass of the CO2(g) sample when the cylinder is adjusted to a volume of 100. milliliters.*
Base your answers to questions 62 through 65 on the information below and on your knowledge of chemistry.
Cobalt-60 is an artifi cial isotope of Co-59. The incomplete equation for the decay of cobalt-60, including beta and gamma emissions, is shown below.
Explain, in terms of both protons and neutrons, why Co-59 and Co-60 are isotopes of cobalt.*
Compare the penetrating power of the beta and gamma emissions.*
Complete the nuclear equation below for the decay of cobalt-60 by writing a notation for the missing product.
Based on Table N, determine the total time required for an 80.00-gram sample of cobalt-60 to decay until only 10.00 grams of the sample remain unchanged.*
Base your answers to questions 66 through 69 on the information below and on your knowledge of chemistry.
During a laboratory activity, appropriate safety equipment was used and safety procedures were followed. A laboratory technician heated a sample of solid KClO3 in a crucible to determine the percent composition by mass of oxygen in the compound. The unbalanced equation and the data for the decomposition of solid KClO3 are shown below.
Write a chemical name for the compound that decomposed.*
Based on the lab data, show a numerical setup to determine the number of moles of O2 produced. Use 32 g/mol as the gram-formula mass of O2.*
Based on the lab data, determine the mass of KCl produced in the reaction.*
Balance the equation below for the decomposition of KClO3, using the smallest whole-number coefficients.
Base your answers to questions 70 through 73 on the information below and on your knowledge of chemistry.
A bottled water label lists the ions dissolved in the water. The table below lists the mass of some ions dissolved in a 500.-gram sample of the bottled water.
State the number of significant figures used to express the mass of hydrogen carbonate ions in the table above.*
Based on Table F, write the formula of the ion in the bottled water table that would form the least soluble compound when combined with the sulfate ion.*
Show a numerical setup for calculating the parts per million of the Na+ ions in the 500.-gram sample of the bottled water.*
Compare the radius of a Mg2+ ion to the radius of a Mg atom.*
Base your answers to questions 74 through 77 on the information below and on your knowledge of chemistry.
Ethyl ethanoate is used as a solvent for varnishes and in the manufacture of artifi cial leather. The formula below represents a molecule of ethyl ethanoate.
Identify the element in ethyl ethanoate that makes it an organic compound.*
Write the empirical formula for this compound.*
Write the name of the class of organic compounds to which this compound belongs.*
Determine the number of electrons shared in the bond between a hydrogen atom and a carbon atom in the molecule.*
Base your answers to questions 78 through 80 on the information below and on your knowledge of chemistry.
An operating voltaic cell has magnesium and silver electrodes. The cell and the ionic equation representing the reaction that occurs in the cell are shown below.
State the purpose of the salt bridge in this cell.*
Write a balanced equation for the half-reaction that occurs at the magnesium electrode in this cell.*
Explain, in terms of electrical energy, how electrolysis reactions differ from voltaic cell reactions.*
Base your answers to questions 81 through 85 on the information below and on your knowledge of chemistry.
In a laboratory investigation, an HCl(aq) solution with a pH value of 2 is used to determine the molarity of a KOH(aq) solution. A 7.5-milliliter sample of the KOH(aq) is exactly neutralized by 15.0 milliliters of the 0.010 M HCl(aq). During this laboratory activity, appropriate safety equipment is used and safety procedures are followed.
Determine the pH value of a solution that is ten times less acidic than the HCl(aq) solution.*
State the color of the indicator bromcresol green if it is added to a sample of the KOH(aq) solution.*
Complete the equation below by writing the chemical formula for each product.
Show a numerical setup for calculating the molarity of the KOH solution.*
Explain, in terms of aqueous ions, why 15.0 mL of a 1.0 M HCl(aq) solution is a better conductor of electricity than 15.0 mL of a 0.010 M HCl(aq) solution.*