elative masses of atoms? There are not that many different kinds of atoms and so it's important to know how they relate to one another. Correct! It provides information about how many atoms two samples have relative to each other It provides an indication of how the different atoms will interact Because the mass of an atom is directly related to its chemical properties. Question 27 0 / 1 pts Which has the greatest number of molecules? 28 g of nitrogen, N2 32 g of oxygen, O2 Correct Answer 32 g of methane, CH4 You Answered 38 g of fluorine, F2 Question 28 1 / 1 pts If it takes 20 beryllium atoms to equal the mass of two krypton atoms, what is the relative mass of beryllium compared to krypton? Correct! 1/10 1/20 40 times 100 times 10 times Question 29 1 / 1 pts Given the following generic chemical reaction, which is correct X _ Y X is the product. Correct! Y is the product. _ is the product. Both X and Y are the products. Both X and Y are the reactants. Question 30 1 / 1 pts According to the following balanced chemical equation, if you want to generate two moles of H2O how many grams of O2 do you need? 2 H2 + O2 _ 2 H2O Correct! 32 16 8 4 6.022 _ 1023 Question 31 1 / 1 pts In a chemical equation the coefficients ________. of the reactants should always sum up to those of the products appear as subscripts Correct! appear before the chemical formulas Two of the above are correct. Question 32 1 / 1 pts What is the number of moles of H2O produced if you combust one mole of CH4 according to the following balanced equation? CH4 + 2 O2 _ CO2 + 2 H2O 8 moles 6 moles 4 moles Correct! 2 moles Question 33 1 / 1 pts What is the formula mass of sulfur dioxide? about 16 amu about 32 amu about 60 amu Correct! about 64 amu Question 34 1 / 1 pts How many bonds (in total) between nitrogen and hydrogen are formed if you react nitrogen with hydrogen according to the following reaction? N2 + 3H2 _ 2 NH3 1 4 3 Correct! 6 8 Question 35 0 / 1 pts How many grams of water, H2O, can be produced by the reaction of 8 grams of oxygen, O2, and 8 grams of hydrogen, H2? 16 grams 10 grams Correct Answer 9 grams You Answered 8 grams Question 36 1 / 1 pts The ________ is what needs to be overcome in a reaction so that it can proceed to the products. bond energy catalyst entropy thermodynamics Correct! activation energy Question 37 1 / 1 pts What is the number of moles of H2O produced if you combust 0.5 mole of CH4 according to the following balanced equation? CH4 + 2 O2 _ CO2 + 2 H2O 2 moles 4 moles 6 moles 8 moles Correct! 1 mole Question 38 1 / 1 pts Which has more atoms: 17.031 g of ammonia, NH3 (17.031 amu), or 72.922 g of hydrogen chloride, HCl (36.461 amu)? 17.031 g of NH3 has more atoms than 72.922 g of HCl 72.922 g of HCl has more atoms than 17.031 g of NH3 Correct! 72.922 g of HCl and 17.031 g of NH3 have about the same number of atoms. Not enough information is given. Question 39 0 / 1 pts Balance the following chemical equation. ____ N2 + ____ H2 _ ____ NH3 Correct Answer 1, 3, 2 1, 2, 3 You Answered 3, 2, 1 2, 6, 4 1/2, 3/2, 1 Question 40 0 / 1 pts How many grams of water, H2O, can be produced from the reaction of 25.0 grams of hydrogen, H2, and 225 grams of oxygen, O2? You Answered 250 grams Correct Answer 225 grams 200 grams 25 grams Question 41 1 / 1 pts Which of the following has the greatest mass? Correct! 1 mole of Pb 1 mole of H2 1 mole of Be 1 mole of Na All have the same mass. Question 42 1 / 1 pts Fourteen grams of nitrogen, N2, (N, atomic mass 14 amu) contains ________. Correct! 1 mole of nitrogen atoms 0.5 moles of nitrogen atoms 0.25 moles of nitrogen atoms Not enough information is given Question 43 1 / 1 pts How many moles of water, H2O, are produced from the reaction of 16 grams methane, CH4, with an unlimited supply of oxygen, O2. How many grams of water is this? CH4 + 2H 2 O_ CO2 + 2 H2O 0.889 mole, which is 16 grams 2.0 moles of water, which is 32 grams Correct! 2.0 moles of water, which is 36 grams 1.0 mole of water, which is 18 grams Question 44 1 / 1 pts If it takes three carbon atoms to equal the mass of one chlorine atom, what mass of chlorine do you need to equal the number of atoms in one kilogram of carbon? Correct! 1/3 of a kg 30 kg 1 kg 3 kg 6 kg Answer: A Diff: 1 Learning Obj: 9.2 Global Obj: G-4 Question 45 1 / 1 pts According to the following balanced chemical equation, if you want to generate two moles of H2O , how many molecules of O2 do you need? 2 H2 + O2 _ 2 H2O 1 2 1/2 4 Correct! 6.022 _ 1023 Question 46 1 / 1 pts How is Avogadro's number related to the numbers on the periodic table? Correct! The atomic mass listed is the mass of Avogadro's number's worth of atoms. The masses are all divisible by Avogadro's number, which gives you the weight of one mole. The periodic table tells you the mass of one atom. From that, and Avogadro's number you know the number of moles. The periodic table only gives us atomic numbers, not atomic mass. Question 47 1 / 1 pts What is the formula mass of a molecule of C6H12O6? Correct! 180 amu 24 amu 29 amu 168 amu Question 48 1 / 1 pts Seven grams of nitrogen, N2, (N, atomic mass 14 amu) contains ________. 1 mole of nitrogen atoms Correct! 0.5 moles of nitrogen atoms 0.25 moles of nitrogen atoms Not enough information is given Question 49 1 / 1 pts What is the number of molecules of O2 consumed if you combust one mole of CH4 according to the following balanced equation? CH4 + 2 O2 _ CO2 + 2 H2O 1 molecule 2 molecules 6.022 _ 1023 molecules Correct! 1.204 _ 1024 molecules Question 50 1 / 1 pts How does a catalyst increase the rate of a reaction? Correct! It lowers the activation energy. It is neither created nor consumed in a reaction. It has nothing to do with the rate of reaction. It increases the energy difference between the reactants and products.