9. (a) Define each of the following terms: (i) actual yield and (ii) percentage yield (ii)theoretical yield (b) Ozone (O_(3)) in the stratosphere can react with nitric oxide (NO) that is discharged from the high altitude planes according to the following equation. O_(3(g))+NO_((g))arrow O_(2(g))+NO_(2(g)) If 130.32 Kg of Ozone gas were reacted with 34 Kg of nitrogen (ii) oxide, NO. (i)Determine the mass (in grams) of NO_(2) that would be produced. (N=14,O=16) (2 marks) (ii)Deduce the limiting reagent in the above reaction. Explain your answer. (3 marks) (iii)Calculate the mass of excess reagent remaining at the end of the reaction. (2 marks) (iv) If 45 kg of NO_(2) is actually produced.Calculate the percentage yield of NO_(2) (2 marks) 10. (a)Define the following terms: (i) ionic radius (ii)ionization energy (iii)atomic radius (iv) electron affinity (6 marks) (b)How does the atomic and ionic radius change as we move from (i) Left to right across the period and (ii) from top to bottom in a group? Use the second and the third periods in the periodic table and the group IA and 7A as examples to illustrate your explanation. (5 marks) (c) Arrange the following atoms, cations , and anions in order of decreasing atomic and anionic radius (i)Na, AL , P, Cl, Mg (ii) Cl^-,P^3-,Na^+,Al^3+,Mg^2+ (Atomic numbers: Na=11,Cl=17,Al=13,P=15,Mg=12,) (4 marks) (6 mark)

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9. (a) Define each of the following terms: (i) actual yield and (ii) percentage yield (ii)theoretical yield (b) Ozone (O_(3)) in the stratosphere can react with nitric oxide (NO) that is discharged from the high altitude planes according to the following equation. O_(3(g))+NO_((g))arrow O_(2(g))+NO_(2(g)) If 130.32 Kg of Ozone gas were reacted with 34 Kg of nitrogen (ii) oxide, NO. (i)Determine the mass (in grams) of NO_(2) that would be produced. (N=14,O=16) (2 marks) (ii)Deduce the limiting reagent in the above reaction. Explain your answer. (3 marks) (iii)Calculate the mass of excess reagent remaining at the end of the reaction. (2 marks) (iv) If 45 kg of NO_(2) is actually produced.Calculate the percentage yield of NO_(2) (2 marks) 10. (a)Define the following terms: (i) ionic radius (ii)ionization energy (iii)atomic radius (iv) electron affinity (6 marks) (b)How does the atomic and ionic radius change as we move from (i) Left to right across the period and (ii) from top to bottom in a group? Use the second and the third periods in the periodic table and the group IA and 7A as examples to illustrate your explanation. (5 marks) (c) Arrange the following atoms, cations , and anions in order of decreasing atomic and anionic radius (i)Na, AL , P, Cl, Mg (ii) Cl^-,P^3-,Na^+,Al^3+,Mg^2+ (Atomic numbers: Na=11,Cl=17,Al=13,P=15,Mg=12,) (4 marks) (6 mark)

Answer 1

9. (a) (i) Actual yield: The actual yield is the amount of product that is actually formed when the reaction is carried out in an experiment. It is usually less than the theoretical yield due to factors such as incomplete reactions, side reactions, or losses during the experiment.(ii) Percentage yield: The percentage yield is the ratio of the actual yield to the theoretical yield, multiplied by 100. It is a measure of the efficiency of a reaction and is calculated using the formula: Percentage yield = (Actual yield / Theoretical yield) x 100.(iii) Theoretical yield: The theoretical yield is the amount of product that would be formed if the reaction were 100% efficient, based on the stoichiometry of the balanced chemical equation.(b) (i) To determine the mass of NO2 produced, we need to use stoichiometry and the molar masses of O3 and NO. The balanced equation shows that 1 mole of O3 reacts with 1 mole of NO to produce 1 mole of NO2. Using the molar masses of O3 (48 g/mol) and NO (30 g/mol), we can calculate the mass of NO2 produced as follows:Mass of NO2 = (130.32 kg O3 x 1000 g/kg) / (48 g/mol) x (30 g/mol) / (1000 g/kg) = 82.5 kg or 82500 g(ii) To determine the limiting reagent, we need to compare the mole ratio of and NO. The mole ratio is calculated by dividing the mass of each reactant by its molar mass. The reactant with the smaller mole ratio is the limiting reagent. In this case, the mole ratio of O3 to NO is (130.32 kg O3 / 48 g/mol) / (34 kg NO / 30 g/mol) = 1.36. Since the mole ratio is greater than 1, NO is the limiting reagent.(iii) To calculate the mass of excess reagent remaining, we need to determine the amount of O3 that reacts with the available NO. Using the stoichiometry of the balanced equation, we can calculate the amount of O3 that reacts as follows:Mass of O3 reacted = (34 kg NO x 1 mol NO / 30 g/mol) x (48 g/mol) / (1 mol O3 / 48 g/mol) = 68 kgThe mass of excess O3 remaining is then:Mass of excess O3 = 130.32 kg - 68 kg = 62.32 kg or 623(iv) To calculate the percentage yield of NO2, we use the formula:Percentage yield = (Actual yield / Theoretical yield) x 100Substituting the given values, we get:Percentage yield = (45 kg NO2 / 82.5 kg NO2) x 100 = 54.55%10. (a) (i) Ionic radius: The ionic radius is the size of an ion, which is an atom or molecule that has gained or lost one or more electrons, resulting in a net charge.(ii) Ionization energy: The ionization energy is the energy required to remove an electron from an atom or ion in its gaseous state, forming a cation.(iii) Atomic radius: The atomic radius is the size of an atom, which is the distance from the nucleus to the outermost electron shell.(iv) Electron affinity: The electron affinity is the energy change that occurs when an electron is added to a neutral atom, forming an anion.(b) (i) As we move from left to right across a period in the periodic table, the atomic radius decreases due to the increasing nuclear charge, which pulls the electrons closer to the nucleus. For example, the atomic radius of sodium (Na) is larger than that of chlorine (Cl) in the second period.(ii) As we move from top to bottom in a group in the periodic table, the atomic radius increases due to the addition of electron shells. For example, the atomic radius of lithium (Li) in group 1A is smaller than that of cesium (Cs) in the same group.(c) (i) Arranging the atoms, cations, and anions in order of decreasing atomic and ionic radius:Na > Mg > Al > P > Cl > Na+ > Mg2+ > Al3+ > P3- > Cl-(ii) Arranging the atoms, cations, and anions in order of decreasing atomic and ionic radius:P3- > Cl- > Na+ > Mg2+ > Al3+

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