ASU BCH 463 (BCH463): Biophysical Chemistry — Module 1 Homework Quiz| Questions and answers - Latest .

ASU BCH 463 (BCH463) Biophysical Chemistry – Module 1 Homework Quiz | Questions & Answers | Latest 2026–2027 1. What are the correct descriptions for particles and waves? A. All of them. B. Waves have the interference phenomenon, but particles do not have this. C. Wave can transport energy, but not mass. D. Particles have masses, but waves do not. 2. For an electron (m = 9.1 × 10⁻³¹ kg) moving at a velocity of 1.0 × 10⁷ m/s, the momentum is: A. 9.1 × 10⁻²³ m B. 73 kg m/sec C. 9.1 × 10⁻²⁴ kg m/sec D. 7.3 × 10⁻¹⁷ m 3. Following above question: If the electron moves at a constant speed without changing its direction, what is the external force acting upon it? 4. Following Problem 2: If the electron moves at a constant speed but changes its direction all the time for a uniform circular motion (radius 1.0 × 10⁻¹⁰ m), what is its centripetal force in 10⁻⁷ N? 5. A 2-kg block is attached to a spring with a spring constant k as 32 N/m horizontally. The object is displaced from its equilibrium by 0.04 m and released from rest. How much time does it take for the block to reach the point at x = 0.02 m? 6. Following the previous question: What is the total energy in this system in Joule? 7. What were the three discoveries that led to the quantum revolution? A. Discrete atomic spectra B. Photoelectric effect C. All of them. D. Blackbody radiation 8. Which one is Newton's equation? (f: force; m: object mass; E: energy; v: velocity; and d: displacement) a. f=ma 2 b. f=ma c. E=0.5mv 2 d. E=fd 2 A. Equation c B. Equation b C. Equation d D. Equation a 9. What is blackbody radiation? A. All of above. B. In classical view, the energy radiation is contributed to the motions of the particles of the system. C. The radiation spectrum is only varied with temperature in classical view. D. Every object can absorb or emit electromagnetic radiations. 10. According to Boltzmann distribution, the ratio of the number of the molecules in a specific state is weighted by a term of: A. ET B. e −E/k B ​ T C. None of the above. D. e −N/k B ​ T 11. How many possible ways that we can assign two heads by tossing five coins? A. 10 B. 20 C. 5 D. 15 12. Following the previous question, what is the probability of obtaining two heads by tossing five coins? A. 0.31 B. 0.61 C. 0.41 D. 0.51 13. For a classical wave, which of the following is NOT true: A. Energy is proportional to wavelength. B. Energy is proportional to amplitude squared. C. Frequency is proportional to velocity. D. Wavelength is proportional to velocity. 14. Presume that the electron performs a uniform circular motion around the hydrogen nucleus. What is the magnitude of the velocity in m/sec? (radius of the circle 5 × 10⁻¹¹ m; period of the motion 1.5 × 10⁻¹⁶ s) A. 2.1 × 10⁶ B. 5.1 × 10⁶ C. 3.1 × 10⁶ D. 4.1 × 10⁶ 15. Followed by the previous question: What is the magnitude of the centripetal acceleration in m/sec²? (radius of the circle 5 × 10⁻¹¹ m; period of the motion 1.5 × 10⁻¹⁶ s) A. 7.7 × 10²³ B. 8.7 × 10²² C. 7.7 × 10²¹ D. 7.7 × 10²² 16. When ultraviolet radiation of wavelength 165 nm strikes a certain metal surface, electrons are ejected with a speed of 1.24 Mm/sec. Calculate the speed of electrons ejected by radiation of wavelength 265 nm in m/s. 17. A photon of radiation of wavelength 305 nm ejects an electron with a kinetic energy of 1.77 eV from a metal. Calculate the longest wavelength of radiation capable of ejecting an electron from the metal in nm. 18. For a photoelectric experiment, the stopping potential was measured as 0.7 V when the light source was kept at a distance of 20 cm. What the stopping potential will be when the light source is kept 40 cm away? A. 2.5 V B. 0.35 V C. 0.7 V D. 1.4 V 19. A mass m of 0.5 kg is attached to a spring with a spring constant k of 200 N/m. The spring is compressed by 0.1 m from its equilibrium position and then released. Determine the maximum velocity of the mass in m/sec as it passes through the equilibrium position. 20. The same question as above: Find the maximum acceleration of the mass (in m/sec²) during the motion. 21. In a gas at thermal equilibrium, the energy levels of the molecules are given by E 1 ​ =3 kJ/mol and E 2 ​ =5 kJ/mol. At a temperature T=300 K, the number of molecules in the energy level E 2 ​ is observed to be N 2 ​ . What is the number of the molecules, N 1 ​ , at the temperature T=300 K? The Boltzmann constant, k B ​ , is given as 8.314 J/(mol K). A. 3.28 N 2 ​ B. 0.802 N 2 ​ C. 2.23 N 2 ​ D. 1.00 N 2 ​