Expert Answers

Description How many moles of HCl are present in 1L of stomach solution that has a pH=1?

Description A temperature increase will result in an increase in gas particle collisions with the walls of the container. TRUE FALSE 2 points Save Answer QUESTION 2 Which of the following gases will diffuse most slowly at 35 degrees Celsius? O2 N2 Cl2 None of the above; they will all diffuse at the same rate. 3 points Save Answer QUESTION 3 According to kinetic molecular theory, there are no forces of attraction between the particles of a liquid. TRUE FALSE 2 points Save Answer QUESTION 4 Of the three main states of matter, only gases can be compressed significantly. TRUE FALSE 2 points Save Answer QUESTION 5 Which of the following substances is a fluid? Air Ice Sand Candles 3 points Save Answer QUESTION 6 In a car cylinder, a piston moves up and down inside a cylinder, causing the substance inside to expand and contract. Which type of substance could be inside the cylinder? Gas only Liquid only Liquid or solid only Gas, liquid, or solid 3 points Save Answer QUESTION 7 The kinetic energy of carbon dioxide molecules in a can of soda is much higher when it is chilled than when it is at room temperature. TRUE FALSE 2 points Save Answer QUESTION 8 Which of the following would have the highest average kinetic energy? Cl2 gas at 35 °C F2 gas at 15 °C O2 gas at 25 °C N2 gas at 50 °C 3 points Save Answer QUESTION 9 The average kinetic energy for a volume of gas can be found by multiplying the following: 3/2, temperature (in Kelvin), and the gas constant, 0.0821 L*atm/mol K. TRUE FALSE 2 points Save Answer QUESTION 10 What is the average kinetic energy of 1 mole of a gas at 125 Kelvin? (R = 8.314 J/K-mol) 1.04 x 103 J 3.12 x 103 J 1.56 x 103 J 1.77 x 103 J Standard atmospheric pressure can be described by many units, including kilopascals, atmospheres, and millimeters of mercury. TRUE FALSE 2 points QUESTION 2 Which of the following shows the correct setup in converting 4.1 atmospheres to kilopascals? 3 points QUESTION 3 The pressure of a gas at 10 degrees Celsius is greater than the pressure of the gas at 30 degrees Celsius. TRUE FALSE 2 points QUESTION 4 If the volume and moles of a container are held constant, the temperature of a gas is inversely proportional to the pressure. TRUE FALSE 2 points QUESTION 5 If the pressure and moles of a gas are held constant, the volume of a gas increases by the same factor as the temperature. TRUE FALSE 2 points QUESTION 6 If the moles and temperature of a gas are held constant, the pressure of a gas doubles when: Volume is halved Volume is quadrupled Volume is doubled Volume is also held constant 3 points QUESTION 7 A balloon containing 0.10 moles of gas has a volume of 2.00 liters. If temperature and pressure remain constant, the new volume will be 3.00 liters when you add 0.15 moles of gas to the balloon. TRUE FALSE 2 points QUESTION 8 When using the ideal gas constant value, R = 0.0821, in an ideal gas law calculation, the units of volume may be expressed in milliliters or liters. TRUE FALSE 2 points QUESTION 9 A balloon contains a fixed amount of helium. If the initial conditions are 1.12 liters, 3.00 atmospheres, and 19 degrees Celsius, what will the final volume be when the balloon is exposed to 1.00 atmosphere pressure and 22 degrees Celsius? 0.370 L 0.377 L 2.90 L 3.39 L 3 points QUESTION 10 Initially, a 1.50-liter compressible container of 0.35 moles of a gas exerts a pressure of 740 millimeters of mercury at a temperature of 275 Kelvin. What is the pressure when the container is compressed to 0.50 liters, the moles of gas reduces to 0.20 moles, and the temperature changes to 32 degrees Celsius? 1.1 x 103 mm Hg 1.4 x 103 mm Hg 1.5 x 102 mm Hg 3.9 x 102 mm Hg

Description The equilibrium pressure of H2 over U(s) and UH3(s) between 450 K and 715 K fits the expression ln(p/Pa) = A + B/T + C ln(T/K), with A = 69.32, B =?1.464 × 104 K, and C = ?5.65. Find an expression for the standard enthalpy of formation of UH3(s) and from it calculate ?rCp

Description QUESTION 1 If you know the number of moles in a sample of a substance, which of the following do you also know about that sample? the mass of that sample the volume of that sample the number of representative particles in that sample the coefficient of the substance when in a chemical reaction 3 points Save Answer QUESTION 2 Which contains a greater number of atoms, a mole of silver or a mole of gold? A mole of silver. A mole of gold. They both contain the same number of atoms. The answer cannot be determined without knowing the molar mass of each element. 3 points Save Answer QUESTION 3 How many atoms are in 0.788 moles of sodium hydroxide? 1.42 x 1024 atoms 7.60 x 1023 atoms 4.70 x 1023 atoms 2.36 x 1023 atoms 3 points Save Answer QUESTION 4 How many atoms are in 0.654 moles of lithium chloride? 3.93 x 1023 atoms 7.87 x 1023 atoms 9.20 x 1023 atoms 1.18 x 1024 atoms 3 points Save Answer QUESTION 5 Determine the molar mass of Ca(OH)2. 29.0 g/mol 38.0 g/mol 57.1 g/mol 74.1 g/mol 3 points Save Answer QUESTION 6 Which of the following is the molar mass of NaCl? 28.00 g/mol 58.44 g/mol 811.8 g/mol 3.500 x 1025 g/mol 3 points Save Answer QUESTION 7 If you are given the number of particles in a substance sample, what is the first step you should take to determine how many grams are present in that sample? find the molar mass of the substance convert the grams to particles convert the moles to mass convert the number of particles to moles 3 points Save Answer QUESTION 8 If you are given the mass of a substance sample in grams, what is the first step you should take to determine how many representative particles are in that sample? find the molar mass of the substance convert the grams to particles convert the mass to moles convert the moles to particles 3 points Save Answer QUESTION 9 Percent composition identifies the amount (in percent) of each element present in a compound. TRUE FALSE 2 points Save Answer QUESTION 10 The percent composition of acetic acid, HC2H3O2, is: 20% carbon, 2% hydrogen, 27% oxygen 40% carbon, 7% hydrogen, 53% oxygen 23% carbon, 7% hydrogen, 70% oxygen Cannot be determined from the information given 3 points Save Answer QUESTION 11 One way to determine the empirical formula of a compound involves using the percent composition of the compound. TRUE FALSE 2 points Save Answer QUESTION 12 A compound was analyzed and found to contain only 14 grams of calcium, 11 grams of oxygen and roughly 0.7 grams of hydrogen. What is the empirical formula of the compound? Ca2OH CaOH CaO2H Ca(OH)2 3 points Save Answer QUESTION 13 It is possible to determine the molecular formula without the empirical formula. TRUE FALSE 2 points Save Answer QUESTION 14 Phosphoric acid, which is a component of many soft drinks, has a molar mass of 98.00 grams per mole. A sample of phosphoric acid contains 3.1 percent hydrogen, 31.6 percent phosphorus, and 65.3 percent oxygen by mass. What is the molecular formula of phosphoric acid? HPO H2PO2 H3PO4 H6P2O8 3 points Save Answer QUESTION 15 In the equation, 2H2 + O2 Imported Asset 2H2O, which substance(s) are the reactant(s)? H2 O2 H2O H2 and O2 3 points Save Answer QUESTION 16 Which of the following data does a complete and balanced chemical equation NOT reveal? the molar ratios of each of the reactants and products the states of matter for each reactant and product the correctly written formula for each reactant and product the mass of each reactant and product 3 points Save Answer QUESTION 17 If a reactant or product is part of a water solution, then (aq) is placed as a subscript after the chemical symbol for the substance. TRUE FALSE 2 points Save Answer QUESTION 18 Select the properly written and balanced equation for the following chemical reaction: Solid iron (II) sulfide reacts with an aqueous solution of hydrochloric acid to produce hydrogen sulfide gas and solid iron (II) chloride. FeS2 (s)+ 2HCl (aq) Imported Asset 2HS (g) + FeCl2 (s) Fe2S2 (s) + 2HCL(aq) Imported Asset 2HS(g) + Fe2Cl2 (s) FeS (s) + 2HCl (aq) Imported Asset H2S (g) + FeCl2 (s) Fe2S (s) + HCl (aq) Imported Asset HS (g) + Fe2Cl 3 points Save Answer QUESTION 19 Select the properly written and balanced equation for the following chemical reaction: Sodium metal and an aqueous solution of magnesium iodide react to produce an aqueous solution of sodium iodide and magnesium metal. Na(s) + MgI (aq) Imported Asset NaI (aq) + Mg(s) Na(s) + MgI2 (aq) Imported Asset NaI2 (aq) + Mg (s) 2Na (s) + MgI2 (aq) Imported Asset 2NaI (aq) + Mg (s) 2Na (s) + 4MgI (aq) Imported Asset 2NaI2 (aq) + 4Mg(s) 3 points Save Answer QUESTION 20 Write the proper word equation to express the following chemical reaction: 4Fe (s) + 3Sn(NO3)4 (aq) Imported Asset 4Fe(NO3)3 (aq) + 3Sn (s). Press Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac). Path: pWords:0 5 points Save Answer QUESTION 21 What type of reaction is represented by the following chemical equation? CH4 + 2O2 Imported Asset CO2 + 2H2O + heat/light double replacement single replacement combustion decomposition 3 points Save Answer QUESTION 22 Which of the following reactions shows a double replacement reaction for CaBr2 reacting with Na2S? CaBr2 + 2Na2S Imported Asset 2NaSBr + Ca CaBr2 + O2 + Na2S Imported Asset CaO2 + 2NaBr + H2S CaBr2 + Na2S Imported Asset 2NaBr + CaS CaBr2 + Na2S Imported Asset 2CaSBr +2Na 3 points Save Answer QUESTION 23 Which type of reaction is described by the following equation? 2LiCl + MgO Imported Asset Li2O + MgCl2. Explain your reasoning. Press Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac). Path: pWords:0 5 points Save Answer QUESTION 24 Which law requires the balancing a chemical equation? Conservation of molecules Conservation of energy Conservation of mass Conservation of elements 3 points Save Answer QUESTION 25 Determine the atom inventory for the following equation: 2Na2O Imported Asset 4Na + O2. Does this equation follow the law of conservation of mass? Na = 2, O = 1; Na = 4, O = 1; no, this equation does not follow the law of conservation of mass Na = 4, O = 2; Na = 4, O = 2; yes, this equation does follow the law of conservation of mass Na = 4, O = 4; Na = 4, O = 2; yes, this equation does follow the law of conservation of mass Na = 2, O = 2; Na = 4, O = 2; no, this equation does not follow the law of conservation of mass 3 points Save Answer QUESTION 26 In the reaction Fe2O3 + 3CO Imported Asset 2Fe + 3CO2, 10 moles of solid iron and 15 moles of carbon dioxide are produced from 5 moles of iron (III) oxide and 15 moles of carbon monoxide (CO). What is the mole ratio of carbon monoxide to solid iron? 15:10 5:10 3:2 2:1 3 points Save Answer QUESTION 27 Choose the correct coefficients to balance the following equation: __Zn + __HCl Imported Asset __ZnCl2 + __H2. 1, 2, 2, 2 1, 2, 1, 1 2, 4, 2, 2 0, 2, 0, 0 3 points Save Answer QUESTION 28 Choose the correct coefficients to balance the following equation: __CaCO3 + __HCl Imported Asset __CaCl2 + __CO2 + __H2O. 1, 2, 1, 1, 1 2, 4, 2, 1, 1 2, 2, 1, 2, 1 1, 2, 1, 1, 2 3 points Save Answer QUESTION 29 The chemical reaction between aluminum and chlorine produces aluminum chloride:Al (s) + Cl2 (g) Imported Asset AlCl3 (s). 3.0 moles of solid aluminum would be required to react with 3.0 moles of chlorine gas. TRUE FALSE 2 points Save Answer QUESTION 30 What is the mole ratio of oxygen to water in the following equation?C3H8 + 5O2 Imported Asset 3CO2 + 4H2O 10:8 10:9 5:4 7:7 3 points Save Answer QUESTION 31 If 5.50 moles of calcium carbide (CaC2) react with an excess of water, how many moles of acetylene (C2H2) will be produced? The balanced equation for this reaction is CaC2 + 2H2O Imported Asset Ca(OH)2 + C2H2. 0.0800 moles 5.50 moles 11.0 moles 143 moles 3 points Save Answer QUESTION 32 According to the following balanced chemical reaction, CsF(s) + XeF6(s)2 Imported Asset CsXeF7(s), 12.5 moles of CsF are reacted with 10.0 moles of XeF6. How many moles of the product will be produced? 10.0 moles 12.5 moles 3.97 x 103 moles 4.96 x 103 moles 3 points Save Answer QUESTION 33 One method to produce nitrogen in the lab is to react ammonia with copper (II) oxide: NH3(g) + CuO(s) Imported Asset Cu(s) + H2O(l) + N2(g). After using 40.0 grams of NH3, 15.5 grams of N2 are produced. What is the percent yield of nitrogen in the reaction?

Description QUESTION 41 The chemical symbol Kr stands for kryptonite. TRUE FALSE 2 points QUESTION 42 The chemical symbol of silver is: Si S Ar Ag 3 points QUESTION 43 The chemical symbol, Na, represents the element: Sodium Nitrogen Nadon Lanthanum 3 points QUESTION 44 The element, tungsten, is represented by which of the following chemical symbols? W T Tu Tn 3 points QUESTION 45 The proper name for O2- is oxygen ion. TRUE FALSE 2 points QUESTION 46 The proper name for Fe2+ is ferride ion. TRUE FALSE 2 points QUESTION 47 Which of the following describes the specific vanadium ion in the compound, VO2? Vanadide ion Vanadium (II) ion Vanadium (I) ion Vanadium (IV) ion 3 points QUESTION 48 Which of the following describes the specific copper ion in the compound, CuCl? Cupride ion Copper (I) ion Copper (II) ion Cupride (I) ion 3 points QUESTION 49 Which of the following describes the anion in the compound MgO? Mg1+ Mg2+ O1? O2? 3 points QUESTION 50 Which of the following describes the specific iron ion in the compound, FeO? Ferride ion Iron (I) ion Iron (II) ion Ferride (I) ion 3 points QUESTION 51 The proper name for SrO is strontium oxide. TRUE FALSE 2 points QUESTION 52 The proper name for CH4 is monocarbon tetrahydride. TRUE FALSE 2 points QUESTION 53 The proper name for AlCl3 is: Aluminum trichloride Monoaluminum trichloride Aluminum chloride Aluminum chlorine 3 points QUESTION 54 The proper name for VO2 is: Vanadium oxide Vanadium (II) oxide Vanadium (I) oxide Vanadium (IV) oxide 3 points QUESTION 55 The formula for xenon tetrafluoride is: XeF Xe4F XeF4 Xe4F4 3 points QUESTION 56 The formula for carbon dioxide is: CO C2O CO2 C2O2 3 points QUESTION 57 The sharing or transferring of outer valence electrons between atoms results in a chemical bond. TRUE FALSE 2 points QUESTION 58 The bond exhibited between two fluorine atoms is an example of an ionic bond. TRUE FALSE 2 points QUESTION 59 The bond exhibited between nitrogen and oxygen is an example of an ionic bond. TRUE FALSE 2 points QUESTION 60 Which of the following pairs of atoms do NOT exhibit an ionic bond? Xe and F Cs and Cl Mn and F Ba and I 3 points QUESTION 61 Which of the following pairs of atoms do NOT exhibit a covalent bond? O and S C and H Sr and F F and H 3 points QUESTION 62 Which of the following pairs of atoms do NOT exhibit an ionic bond? Cl and Al Cl and B Ca and F Rb and S 3 points QUESTION 63 The Lewis structure of HCl has a double-bond. TRUE FALSE 2 points QUESTION 64 The compound, BF3, has the Lewis structure as shown below: TRUE FALSE 2 points QUESTION 65 The Lewis structure for NH4+ is: 3 points QUESTION 66 The Lewis structure for CO2 is: 3 points QUESTION 67 The compound H2CO, has a Lewis structure of: 3 points QUESTION 68 The Lewis structure for the compound, CH2Cl2, is: 3 points QUESTION 69 Cynthia and Jackie both draw the Lewis structure for F2 as shown below. Which drawing is correct? Explain. Cynthia's Drawing Jackie's Drawing Press Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac). -- Font family -- Andale Mono Arial Arial Black Book Antiqua Comic Sans MS Courier New Georgia Helvetica Impact Symbol Tahoma Terminal Times New Roman Trebuchet MS Verdana Webdings Wingdings -- Font size -- 1 (8pt) 2 (10pt) 3 (12pt) 4 (14pt) 5 (18pt) 6 (24pt) 7 (36pt) -- Format -- Heading Sub Heading 1 Sub Heading 2 Paragraph Formatted Code -- Font family -- -- Font size -- Path: pWords:0 5 points QUESTION 70 Which functional groups are involved in an amino acid? Press Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac). -- Font family -- Andale Mono Arial Arial Black Book Antiqua Comic Sans MS Courier New Georgia Helvetica Impact Symbol Tahoma Terminal Times New Roman Trebuchet MS Verdana Webdings Wingdings -- Font size -- 1 (8pt) 2 (10pt) 3 (12pt) 4 (14pt) 5 (18pt) 6 (24pt) 7 (36pt) -- Format -- Heading Sub Heading 1 Sub Heading 2 Paragraph Formatted Code -- Font family -- -- Font size -- Path: pWords:0

Description QUESTION 1 Which of the following choices is the most conclusive in determining whether a chemical reaction has taken place? a change in color a change in odor a gas was formed a change in the identity of the substance(s) 3 points QUESTION 2 If different products are not created during a process, then a chemical reaction has not occurred. TRUE FALSE 2 points QUESTION 3 Balanced chemical equations provide: the exact quantities of the reactants and products information about how fast the reaction will proceed ratios of atoms, ions, molecules and/or formula units used in the equation an outline of how the substances change from reactants to products 3 points QUESTION 4 The symbol(s) are used to indicate that heat is produced as a result of the reaction. TRUE FALSE 2 points QUESTION 5 From the balanced chemical equations listed below, which equation best expresses the following word equation: The reversible reaction in which solid calcium carbonate yields solid calcium oxide plus carbon dioxide gas? CaCO3 (s) CaO (s) + CO2 (g) CaCO3 (s) CaO (s) + CO2 (g) CaO (s) + CO2 (g) CaCO3 (s) CaClO3 CaClO (s) + O2 (g) 3 points QUESTION 6 From the balanced chemical equations listed below, which equation best expresses the following word equation: Hydrogen gas plus oxygen gas yields water vapor plus energy? 2H2O (g) 2H2 (g) + O2 (g) + energy 2H + O 2HO + energy 2H2 (g) + O2 (g) 2H2O (g) + energy 2H2 (g) + O2 (g) + energy 2H2O (l) 3 points QUESTION 7 Which type of chemical reaction does this equation exemplify? synthesis decomposition double replacement single replacement 3 points QUESTION 8 Which type of chemical reaction does this equation exemplify? synthesis decomposition double replacement single replacement 3 points QUESTION 9 Which type of chemical reaction does this equation exemplify? synthesis decomposition combustion double replacement 3 points QUESTION 10 Match the type of chemical reaction with the appropriate skeleton equation. - A. B. C. D. E. A + B ABRead Answer Items for Question 10 - A. B. C. D. E. AB A + BRead Answer Items for Question 10 - A. B. C. D. E. A + BX AX + BRead Answer Items for Question 10 - A. B. C. D. E. AX + BY AY + BXRead Answer Items for Question 10 - A. B. C. D. E. 2A + O2 2AORead Answer Items for Question 10 Answer A. Single Replacement B. Decomposition C. Synthesis D. Combustion E. Double Replacement QUESTION 1 Balanced chemical equations show: the reactants entering the reaction the products formed by the reaction the ratios of moles needed to balance the reactants and products all of the above 3 points Save Answer QUESTION 2 In the equation, CaCO3 (s) Imported Asset CaO (s) + CO2 (g), the mass of the reactants: is greater than the mass of the products because a gas is released on the product side of the equation is less than the mass of the products because the mass of the gas is not included on the reactant side of the equation is the same as the mass of the products has no relationship to the mass of the products 3 points Save Answer QUESTION 3 When balancing a chemical equation, where should a coefficient be placed? in front of formulas and element symbols in front of individual elements and behind individual compounds behind formulas and element symbols by the lower right hand corner of element or compound formulas, to indicate numbers of atoms 3 points Save Answer QUESTION 4 Coefficients should always: be whole numbers use the lowest possible ratios use the values of 1, 2, 3, or 4 both choices a and b 3 points Save Answer QUESTION 5 What is the molar ratio for the following equation after it has been properly balanced? ____SiO2 + ____C Imported Asset ____ SiC + ____CO Reactants: SiO2 = 1, C = 3; Products: SiC = 1, CO = 2 Reactants: SiO2 = 1, C = 2; Products: SiC = 1, CO = 2 Reactants: SiO2 = 2, C = 3; Products: SiC = 2, CO = 2 Reactants: SiO2 = 3, C = 3; Products: SiC = 3, CO = 2 3 points Save Answer QUESTION 6 What is the molar ratio for the following equation after it has been properly balanced? ____C3H8 + ____O2 Imported Asset ____CO2 + ____ H2O Reactants: C3H8 = 2, O2 = 5; Products: CO2 = 6 and H2O = 4 Reactants: C3H8 = 1, O2 = 5; Products: CO2 = 3 and H2O = 4 Reactants: C3H8 = 1, O2 = 8; Products: CO2 = 3 and H2O = 4 Reactants: C3H8 = 1, O2 = 5; Products: CO2 = 3 and H2O = 5 3 points Save Answer QUESTION 7 What is the atom inventory for the following equation after it has been properly balanced? ____Li + ____BaF2 Imported Asset ____LiF + ____Ba Reactants: Li = 2, Ba = 1, F = 2; Products: Li = 2, Ba = 1, F = 1 Reactants: Li = 1, Ba = 2, F = 2; Products: Li = 1, Ba = 2, F = 2 Reactants: Li = 2, Ba = 1, F = 2; Products: Li = 2, Ba = 1, F = 2 Reactants: Li = 1, Ba = 1, F = 2; Products: Li = 1, Ba = 1, F = 2 3 points Save Answer QUESTION 8 If the combined mass of the reactants is 100 grams, then which of the following MUST be true? the combined mass of the products is 100 grams each product has a mass of 100 grams each reactant has the same mass as each product each reactant must produce 100 grams of product 3 points Save Answer QUESTION 9 In the equation, A + B Imported Asset C + D, if the sum of the masses of reactants A and B is known, and the mass of product C is known, then the mass of product D can be calculated. TRUE FALSE 2 points Save Answer QUESTION 10 Every chemical compound has a formula, which cannot be altered when balancing chemical equations. TRUE FALSE 2 points Save Answer QUESTION 11 A balanced chemical equation must account for every atom involved in a chemical reaction. TRUE FALSE Given the reaction, PCl3 + Cl2 Imported Asset PCl5, if 3.00 moles of Cl2 are used, then how many moles of PCl5 are made?6.00 moles5.00 moles3.00 moles1.00 mole3 points Save AnswerQUESTION 2Given the balanced equation, 2 SO2 + O2 Imported Asset 2 SO3, what is the molar ratio of O2 to SO3?2:11:22:22:33 points Save AnswerQUESTION 3Given the balanced equation, 4 NH3 + 3 O2 Imported Asset 2 N2 + 6 H2O, what is the molar ratio of NH3 to N2?3:24:62:44:23 points Save AnswerQUESTION 4Using the equation, C5H12 + 8O2 Imported Asset 5CO2 + 6H2O, if an excess of pentane (C5H12) were supplied, but only 4 moles of oxygen were available, how many moles of water would be produced?1 mole2 moles3 moles6 moles3 points Save AnswerQUESTION 5Using the equation, C5H12 + 8O2 Imported Asset 5CO2 + 6H2O, if 10 moles of carbon dioxide are produced, how many moles of pentane (C5H12) would need to be supplied?2 moles0.5 mole5 moles10 moles3 points Save AnswerQUESTION 6Using the equation, 4Fe + 3O2 Imported Asset 2Fe2O3, if 8 moles of iron and oxygen from the air were available, how many moles of iron (III) oxide would be produced?4 moles5 moles6 moles8 moles3 points Save AnswerQUESTION 7When magnesium metal and an aqueous solution of hydrochloric acid combine, they produce an aqueous solution of magnesium chloride and hydrogen gas. Using the equation, Mg (s) + 2HCl (aq) Imported Asset MgCl2 (aq) + H2 (g), if 72.9 g of Mg and 146.0 g of HCl are allowed to react, identify the limiting reagent.MgHClMgCl2H23 points Save AnswerQUESTION 8When magnesium metal and an aqueous solution of hydrochloric acid combine, they produce an aqueous solution of magnesium chloride and hydrogen gas. Using the equation, Mg (s) + 2HCl (aq) Imported Asset MgCl2 (aq) + H2 (g), if 24.3 g of Mg and 75.0 g of HCl are allowed to react, calculate the mass of MgCl2 that is produced.75.0 g95.1 g99.3 g104 g3 points Save AnswerQUESTION 9The number of moles of the reagent in excess can be used to calculate the moles of the products of the reaction.TRUEFALSE2 points Save AnswerQUESTION 10In the manufacturing process of sulfuric acid, sulfur dioxide is reacted with oxygen to produce sulfur trioxide. Using the equation, 2SO2 (g) + O2 Imported Asset 2SO3 (g), if 64.06g of sulfur dioxide is given an opportunity to react with an excess of oxygen to produce 75.00 g of sulfur trioxide, what is the percent yield of this reaction?46.83%60.25%75.55%93.68%3 points Save AnswerQUESTION 11Red mercury (II) oxide decomposes to form mercury metal and oxygen gas according to the following equation: 2HgO (s) Imported Asset 2Hg (l) + O2 (g). If 3.00 moles of HgO decompose to form 1.25 moles of O2 and 503 g of Hg, what is the percent yield of this reaction?41.6%62.5%83.3%96.9%3 points Save AnswerQUESTION 12Red mercury (II) oxide decomposes to form mercury metal and oxygen gas according to the following equation: 2HgO (s) Imported Asset 2Hg (l) + O2 (g). If 4.00 moles of HgO decompose to form 1.50 moles of O2 and 603 g of Hg, what is the percent yield of this reaction?26.7%53.4%75.0%95.5%3 points Save AnswerQUESTION 13The percent yield for a chemical reaction can not be calculated until the reaction is completed.TRUEFALSE2 points Save AnswerQUESTION 14The theoretical yield for a chemical reaction can not be calculated until the reaction is completed.TRUEFALSE

Description There is a total of five questions pretaining to chemical reactions. All work must be 100% original. If not, the work will not be accepted.

Description Make sure that you are showing each step of your work. The half-life of cobalt-60 is 5.27 years. How many milligrams of cobalt-60 remain after 52.7 years if you start with 15 mg? A sample contains 12.0 mg of an unknown element. After 4.46 × 109 years, the sample will contain 3.00 mg of the unknown element. What is the half-life of the unknown element? "Make sure to show your work, and your answers should be provided with the correct amount of significant figures."

Description   "Perform the calculations, make sure to show your work, and your answers should be provided with the correct amount of significant figures." Determine the hydronium and hydroxide ion concentrations in a solution that is 2.0 × 10-2 M NaOH Determine the pH of a solution that is 5.0 × 10-4 M HNO3+ Determine the pH of a 3.45 × 10-2 M Sr(OH)2 solution. The pH of a solution is determined to be 7.0. What is the hydronium ion concentration of this solution? The pH of an aqueous solution is measured as 5.00 Calculate the [H3O+] and the [OH-].

Description Read the Experiment attached and answer these 11 Questions: 1.  What are we looking to find in this experiment? 2.  What will you measure in this experiement to determine the molar mass of your unknown solid? 3.  How will you use the freezing point depression information to determine the molar mass of the unknown solid? 4.  What theories or equations will allow you to determine the molar mass of the unknown solid? 5.  What data will be collected in this experiment and how will it be used to determine the molar mass of the unknown solid? 6.  Describe the important techniques that will be used to collect the data in this experiement? 7.  What important assumptions are made about the unknown solid in order to determine its molar mass using freezing point depression? 8.  What is the expected outcome of this experiment? What are some possible unexpected outcomes? 9.  What is the scientific relationship between freezing point depression and the amount of solid that will allow us to correctly determine the molar mass? 10.  What important variables need to be accounted for so that only the relationship between freezing point depression and the mass of the unknown solid is being measured? 11.  What special safety precautions do you need to be aware of for this experiment?