Chemistry Concepts and Calculations, Exams of Nursing

Download Chemistry Concepts and Calculations and more Exams Nursing in PDF only on Docsity!

CHEM 101 FINAL EXAM IVY TECH

EXAM PRACTICE EXAM FROM ACTUAL

EXAM QUESTIONS AND CORRECT

DETAILED ANSWERS (VERIFIED

ANSWERS) |ALREADY GRADED A+

A lead ball has a mass of 55.0 grams and a density of 11. g/cm3. What is the volume of the ball? Correct Answer 4.82 mL When the value 4.449 is rounded to two significant figures, the number should be reported as: Correct Answer 4. The correct number of significant figures in the number 865, is: Correct Answer ambiguous How many inches are in 2.80 ft? Correct Answer 3 3. Which of the following would NOT be considered a correct conversion factor? Correct Answer 1 pair of shoes = 1 shoe Suppose a boat engine leaks 938 mL of oil into a lake. The mass of this spilled oil is 823 g. The oil will not mix with the lake water. Which statement is true? Correct Answer The oil will float because its density of 0.877 g/mL is less than the density of water. Which state of matter has indefinite shape and is compressible? Correct Answer gas A solution is an example of a (an): Correct Answer homogeneous mixture

Which of the following is NOT an example of a physical property? Correct Answer Water can form hydrogen and oxygen under electrolysis conditions. Which of the following is a homogeneous mixture? Correct Answer stainless steel When methane is burned with oxygen the products are carbon dioxide and water. If you produce 36 grams of water and 44 grams of carbon dioxide from 16 grams of methane, how many grams of oxygen were needed for the reaction? Correct Answer 64 Which of the following statements about matter is FALSE? Correct Answer Matter is smooth and continuous. Which of the following items is a chemical property? Correct Answer the tarnishing of a copper statue Which state of matter has atomic spacing that is close together and definite shape? Correct Answer solid All of the following can be considered physical properties EXCEPT: Correct Answer flammability Which of the following elements has an atomic number of 4? Correct Answer Be What is the charge on the ion formed by aluminum? Correct Answer 3+ An atom containing 7 protons, 8 neutrons, and 7 electrons: Correct Answer is charge-neutral.

Which of the following statements about atoms is FALSE? Correct Answer All of the above statements are true. Isotopes are: Correct Answer atoms of the same element that have different number of neutrons. How many neutrons are present in C-14? Correct Answer 8 What is the definition of a scientific theory? Correct Answer a model that explains the underlying reasons for observations and laws What term best describes a brief statement that summarizes many past observations and predicts new ones? Correct Answer scientific law Which of the following is an example of a scientific law? Correct Answer In a chemical reaction, matter is neither created nor destroyed. Which of the following would be considered a theory? Correct Answer Helium balloons float because helium is less dense than air. The key to success in chemistry is: Correct Answer all of the above A plastic block has dimensions of 2.2 cm x 3.0 cm x 1.5 cm and a mass of 12.4 grams. Will the block float in water and why? Correct Answer No, because the density of the block is 1.3 g/mL which is greater than the density of water. Given the density of Au is 19.3 g/cm3, determine the mass of gold (in grams) in an ingot with the dimensions of 10.0 in x 4.00 in x 3.00 in. Correct Answer 3.80 x 104

The distance between the two hydrogen atoms in a molecule of water is 0.000000000172 m. Express this distance in scientific notation. Correct Answer 1.72 x 10-10 m How many grams are in 1.48 x 107 μg? Correct Answer 14. The correct decimal representation of 6.453 x 103 is: Correct Answer 6, How many significant digits should be reported in the answer to the following question? (4.3-3.7) x 12.3= Correct Answer 1 The correct scientific notation for the number 0.00050210 is: Correct Answer 5.0210 x 10- 4 Which measurement below represents the heaviest mass? Correct Answer 1 Mg Determine the answer to the following equation with correct number of significant figures: 2.02+8.102-0.0297= Correct Answer 10. When an atom loses an electron, the resulting particle is called: Correct Answer a cation How many protons and electrons are present in O2-? Correct Answer 8 protons and 10 electrons Which of the following is a main-group element? Correct Answer none of the above How many protons and neutrons are in Cl-37? Correct Answer 17 protons, 20 neutrons

The "d" subshell can hold a maximum of ____ electrons Correct Answer 10 How many subshells are there in the n=2 principal shell? Correct Answer 2 How many electrons are unpaired in the orbitals of carbon? Correct Answer 2 The subshell that has three orbitals and can hold up to six electrons is the: Correct Answer p subshell What is the electron configuration for Ga? Correct Answer 1s22s22p63s23p64s23d104p The principal quantum number (n): Correct Answer specifies the principal shell of the orbital "When filling orbitals of equal energy, electrons fill them singly first with parallel spins" This is known as: Correct Answer Hund's rule Which statement below does NOT follow the Bohr Model? Correct Answer The energy emitted from a relaxing electron can have any wavelength The subshell that has five orbitals and can hold up to ten electrons is the: Correct Answer d subshell How many subshells are there in the n=4 principal shell? Correct Answer 4

The electronegativity value for Mg is 1.2 and the value for O is 3.5. Based on these values, what type of bond is expected for a compound formed between Mg and O? Correct Answer ionic The electronegativity value for N is 3.0 and that for O 3.5. Based on these values, which of the following statements is TRUE about the compound NO? Correct Answer NO is a polar covalent compound Which of the following is considered a single electron group? Correct Answer All of the above What is the electron geometry if you have 4 electron groups around the center atom? Correct Answer tetrahedral Which term matches the definition: A separation of charge within a bond? Correct Answer dipole moment How many valence electrons are in the nitrate ion? Correct Answer 24 What is the electron geometry if you have 2 electron groups around the center atom? Correct Answer linear Which compound below is a polar molecule AND has a linear molecular geometry? Correct Answer CO The central atom in the chlorite anion, ClO2- is surrounded by: Correct Answer two bonding and two unshared pairs of electrons Which molecule listed below has a nonpolar covalent bond? Correct Answer H All of the following compounds are soluble in water EXCEPT: Correct Answer PbCl

If you had an aqueous mixture that contained Ag+, K+, and Pb2+ cations, how many different solids could precipitate if a chloride solution was added? Correct Answer 2 Before a chemical equation can be written, one must know: Correct Answer The symbols and formulas of all reactants and products. Which of the following is NOT an acid? Correct Answer none of the above When solid NaCl is stirred into water, which of the following is NOT true? Correct Answer The NaCl will fail to dissociate. The compound sodium sulfate is soluble in water. When this compound dissolves in water, which ion listed below would be present in solution? Correct Answer SO42- Which of the following everyday substances does NOT typically contain an acid? Correct Answer soap What type of a reaction occurs when a hydrochloric acid solution is mixed with a sodium bicarbonate solution? Correct Answer gas evolution Which is a spectator ion from the following complete ionic equation: Ag+(aq)+ NO3-(aq)+Br-(aq)⟶AgBr (s) + K+(aq)+NO3-(aq) Correct Answer K+ Which of the following statements about balancing reactions is FALSE? Correct Answer When coefficients are added the type of compound is changed in the chemical reaction

How many atoms are in 1.50 moles of fluorine gas? Correct Answer 1.81 x 1024 atoms If you have 2.41 x 1024 atoms of copper, how many moles of copper do you have? Correct Answer 4.00 mol Calculate the molar mass of ammonium carbonate, (NH4)2CO3. Correct Answer 96.09 g/mol Which of the following statements about the mole is FALSE? Correct Answer One mole of water contains 1/2 mole of oxygen atoms. How many moles of fluorine are in 3.2 moles of xenon hexafluoride, XeF6? Correct Answer 19.2 mol How many atoms are in 5.80 moles of He? Correct Answer 3.49 x 1024 atoms One mole of ammonium nitrate, NH4NO3, contains: Correct Answer 2 moles of nitrogen atoms 4 moles of hydrogen atoms 3 moles of oxygen atoms How many moles of potassium are in 156.4 g? Correct Answer 4.000 mol What is the mass percent of carbon in oxalic acid, H2C2O4? Correct Answer 26.7% What is the mass (in grams) of 1.95 moles of water, H2O? Correct Answer 35.1 g Which metal atom below cannot form a cation of several different charges? Correct Answer Ba

Suppose that in an ionic compound, "M" represents a metal that could form more than one type of ion. In the formula MF2, the charge of the M ion would be: Correct Answer + What is the name of Ca(NO3)2? Correct Answer calcium nitrate Which formula shows the proper use of parentheses? Correct Answer Ca(NO3) The ionic compound that forms between potassium and oxygen is: Correct Answer K2O What is the formula mass of copper(II) fluoride, CuF2? Correct Answer 101.55 amu What is the name of HNO2? Correct Answer nitrous acid Which formula shown is incorrect for the name given? Correct Answer lithium sulfate: LiSO What would the formula of diiodine pentasulfide be? Correct Answer I2S Choose the pair of names and formulas that do NOT match. Correct Answer all of these are correct What is the formula for an ionic compound made of magnesium and sulfur? Correct Answer MgS How many carbon atoms are in the formula Al2(CO3)3? Correct Answer 3

What is the formula for an ionic compound made of carbon and oxygen? Correct Answer carbon and oxygen do not form an ionic compound What is the name of the compound whose formula is Na2O? Correct Answer sodium oxide Which of the following is a molecular compound? Correct Answer nitrogen monoxide What is the formula mass for potassium nitrate, KNO3? Correct Answer 101.11 amu What is the name of CoS? Correct Answer cobalt(II) sulfide Which of the following statements about chemical formulas is FALSE? Correct Answer The subscripts represent the relative mass of each type of atom in the compound. Carbon is considered which of the following? Correct Answer atomic element What is the proper name for HBr(aq)? Correct Answer hydrobromic acid If the theoretical yield of the reaction below corresponds to 99.2 g and the actual yield was 60.9 g, calculate the percent yield. Given: Li2O + H2O⟶ 2 LiOH Correct Answer 61.4% What is the excess reactant for the following reaction given we have 2.6 moles of HCl and 1.4 moles of Ca(OH)2? Reaction: 2HCl + Ca(OH)2⟶2H2O + CaCl2 Correct Answer Ca(OH)

What is the limiting reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4⟶ 6LiNO3 + Ca3(PO4)2 Correct Answer Ca(NO3) Which of the below statements about global warming is FALSE? Correct Answer If the level of greenhouse gases increases, the temperature will decrease Iron metal reacts with oxygen to produce iron (III) oxide. If you have 12.0 moles of iron for complete reaction, you need: Correct Answer 9.0 moles of O2 and produce 6.0 moles of Fe2O Given that 4 NH3+ 5O2 ⟶ 4 NO + 6 H2O, if 3.00 mol NH3 were made to react with excess of oxygen gas, the amount of H2O formed would be: Correct Answer 4.50 mol. How many moles of chlorine gas are needed to make 0.6 moles of sodium chloride? Given the reaction: 2 Na + Cl2⟶ 2NaCl Correct Answer 0. What is the excess reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4⟶ 6LiNO3 +Ca3(PO4)2 Correct Answer Li3PO Many metals react with halogens to give metal halides. For example, 2 Al (s) + 3 Cl2 (g) ⟶ 2AlCl3 (s) If you begin with 13.5 g of aluminum: Correct Answer you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl Which is the excess reactant in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4?

Reaction: Na2S + CuSO4⟶ Na2SO4 + CuS Correct Answer Na2S Which of the following statements about the quantum-mechanical model is FALSE? Correct Answer Orbitals are specific paths electrons follow The subshell that has three orbitals and can hold up to six electrons is the: Correct Answer p subshell Which orbital would the electron of a ground state hydrogen atom occupy? Correct Answer 1s What is the element in which at least one electron is in the d- orbital? Correct Answer Sc Which statement below does NOT follow the Bohr Model? Correct Answer The energy emitted from a relaxing electron can have any wavelength How many electrons are unpaired in the orbitals of nitrogen? Correct Answer 3 Consider the electron configuration of the ion to determine which ion shown below has an incorrect ionic charge? Correct Answer Al3- Which of the following elements has the electron configuration of 3s23p4 in its outermost shell? Correct Answer S Choose the answer that best completes the following statement: When an aluminum atom reacts so as to attain a noble gas electron configuration, Correct Answer the result is a configuration of 1s22s22p

How many electrons can exist in an orbital? Correct Answer 2 What is the heat of vaporization (kJ/mol) if it takes 3,452 J of heat to completely vaporize 2.68 moles of the liquid at its boiling point? Correct Answer 1. Why is water considered an unusual molecule? Correct Answer water can dissolve many polar and ionic compounds water expands on freezing no molecule of similar size is a liquid at room temperature no molecule of similar size has as high a boiling point Liquids that have high vapor pressure and low boiling points are called: Correct Answer Volatile liquids Which sequence correctly shows the increasing density of the three phases of water? Correct Answer gas < solid < liquid A 250 gram sample of water at the boiling point had 45.0 kJ of heat added. How many grams of water were vaporized? Heat of vaporization for water is 40.6 kJ/mole. Correct Answer 20. Which compound in liquid form will have the highest vapor pressure? Correct Answer CH Which intermolecular force is common to all polar molecules but NOT nonpolar molecules? Correct Answer dipole-dipole forces How much energy does it take to melt a 16.87 g ice cube? ΔHfus= 6.02 kJ/mol Correct Answer 5.64 kJ NaCl is which type of solid? Correct Answer ionic solid

How many kilojoules of heat are needed to completely vaporize 42.8 grams of C4H10O at is boiling point? Given ΔHvap= 26. kJ/mol Correct Answer 15. What volume (L) of 2.00 M KCl solution contains 25.0 g of KCl? Correct Answer 0. We dissolve 2.45 g of sugar in 200.0 g water. What is the mass percent of sugar in the solution? Correct Answer 1.21% How much water would you ADD to 175 mL of 6.00 M hydrochloric acid to prepare a 2.00 M solution of this acid? Correct Answer 350 mL If you add 1.00 mL of pure water to 6.00 mL of 0.750 NaCl solution, what is the concentration of sodium chloride in the diluted solution? Correct Answer 0.642 M Which among the following is NOT true about the solubility of a solid in water? Correct Answer none of the above Suppose a vodka martini contains 30% alcohol with the remaining portion of the drink composed of water. What is the solute in this type of martini? Correct Answer alcohol You need to prepare 2.00 L of 0.100 M Na2CO3 solution. The best procedure is to weigh out: Correct Answer 21.2 g Na2CO and add water until the final solution has a volume of 2.00 L How many grams of LiF would be present in 575 mL of 0.750 M LiF solution? Correct Answer 11. What is the molarity of a solution prepared by dissolving 10.7 g NaI in 0.250 L? Correct Answer 0.

What is the final concentration of a solution prepared by diluting 35.0 mL of 12.0 M HCl to a final volume of 1.20 L? Correct Answer 0.350 M