DSST Physical Sciences 5 — Questions and Answers
Question 1: Which gas law relates volume directly to temperature at constant pressure?
- Boyle's Law
- Charles's Law (Correct answer)
- Dalton's Law
- Henry's Law
Correct answer: Charles's Law
Charles's Law states that V/T = constant when pressure is held fixed (V and T must be in absolute units).
Question 2: What is the term for the energy required to remove one electron from a gaseous atom?
- Electron affinity
- Electronegativity
- Ionization energy (Correct answer)
- Bond dissociation energy
Correct answer: Ionization energy
Ionization energy is the minimum energy needed to remove the outermost electron from a neutral gaseous atom.
Question 3: A 60 W light bulb operates for 10 hours. How much energy does it consume in joules?
- 600 J
- 3,600 J
- 36,000 J
- 2,160,000 J (Correct answer)
Correct answer: 2,160,000 J
Energy = Power × Time = 60 W × 36,000 s = 2,160,000 J.
Question 4: Which subatomic particle determines the chemical identity of an element?
- Neutron
- Electron
- Proton (Correct answer)
- Photon
Correct answer: Proton
The number of protons (atomic number) uniquely identifies each element on the periodic table.
Question 5: What type of reaction produces heat as a product?
- Endothermic
- Isothermal
- Exothermic (Correct answer)
- Adiabatic
Correct answer: Exothermic
Exothermic reactions release energy to the surroundings, causing the temperature of the environment to rise.
Question 6: What is the term for the bending of light as it passes from one medium to another?
- Reflection
- Refraction (Correct answer)
- Diffraction
- Dispersion
Correct answer: Refraction
Refraction occurs because light changes speed when entering a medium with a different index of refraction.
Question 7: In a series circuit with three resistors of 4 Ω, 6 Ω, and 10 Ω, what is the total resistance?
- 2 Ω
- 5 Ω
- 10 Ω
- 20 Ω (Correct answer)
Correct answer: 20 Ω
In series circuits, total resistance = sum of individual resistances: 4 + 6 + 10 = 20 Ω.
DSST Physical Sciences 5
Which gas law relates volume directly to temperature at constant pressure?