Chapter 2 Question 1. A beam of electrons is passing close to a highly negatively charged plate. When the electrons pass close to the plate, they are deflected away from the plate. a. What deflection would you expect, if any, when the experiment is repeated with beams of i protons and ii neutrons? Explain your answers. b. Which subatomic particle (electron, proton or neutron) would deviate the most? Explain your answer. Answer: a) When the experiment is repeated with beams of protons and neutrons, we would not expect any deflection similar to what is observed with electrons. This is because electrons are negatively charged particles, and they experience a force of repulsion when they come close to the highly negatively charged plate. On the other hand, protons are positively charged particles, and neutrons have no charge. Therefore, they would not experience the same repulsive force and would not be deflected. b) The subatomic particle that would deviate the most is the electron. This is because electrons have a much smaller mass compared to protons and neutrons. According to the principles of electromagnetism, the force experienced by a charged particle moving through a magnetic field is proportional to the charge of the particle, its velocity, and the strength of the magnetic field. Since electrons have a smaller mass, they have a higher velocity for a given energy, resulting in a larger deflection when passing through a magnetic field. Protons and neutrons, with their larger masses, would experience less deflection due to their lower velocities. Question 2. Use the information in Table 1.3 to deduce the number of electrons and neutrons in a neutral atom of: a vanadium b strontium c phosphorus Atom vanadium strontium phosphorus Mass number 51 88 31 Proton number 23 38 15 Answer: To deduce the number of electrons and neutrons in a neutral atom, we can use the information provided in Table 1.3. a) Vanadium (V): - Proton number (atomic number) = 23 - Mass number = 51 To find the number of electrons, we can assume that in a neutral atom, the number of electrons is equal to the number of protons. Therefore, vanadium has 23 electrons. To find the number of neutrons, we subtract the number of protons (atomic number) from the mass number: Number of neutrons = Mass number - Atomic number Number of neutrons = 51 - 23 Number of neutrons = 28 Therefore, a neutral atom of vanadium (V) has 23 electrons and 28 neutrons. b) Strontium (Sr): - Proton number (atomic number) = 38 - Mass number = 88 Strontium has 38 electrons and to find the number of neutrons: Number of neutrons = Mass number - Atomic number Number of neutrons = 88 - 38 Number of neutrons = 50 Therefore, a neutral atom of strontium (Sr) has 38 electrons and 50 neutrons. c) Phosphorus (P): - Proton number (atomic number) = 15 - Mass number = 31 Phosphorus has 15 electrons and to find the number of neutrons: Number of neutrons = Mass number - Atomic number Number of neutrons = 31 - 15 Number of neutrons = 16 Therefore, a neutral atom of phosphorus (P) has 15 electrons and 16 neutrons Question 3. Use the Periodic Table in Appendix 1 to help you. a Write isotopic symbols for the following neutral atoms: b bromine-81 c calcium-44 d iron-58 e palladium-110 Answer: a) Isotopic symbols for the following neutral atoms are: b) Bromine-81: ^81Br c) Calcium-44: ^44Ca d) Iron-58: ^58Fe e) Palladium-110: ^110Pd Question 4. 4 Deduce the number of electrons in each of these ions: a 40K+ 19 b 157N3− c 18O2− d 71Ga3+ Answer: