Unit 2 Flashcards
What is the model of the atom discussed?
Electrically neutral with a small nucleus containing protons and neutrons, surrounded by a cloud of electrons.
What are the charges and masses of protons and neutrons?
Protons have a +1 charge and mass of 1 amu; neutrons have a 0 charge and mass of 1 amu.
What is the charge and approximate mass of electrons?
Electrons have a -1 charge and mass of ~1/3000 amu.
What principle explains how atoms interact?
Positive and negative charges attract, while like charges repel (Coulomb’s Law).
Define a force in the context of chemistry.
A push or a pull, also referred to as an interaction.
List the four fundamental types of forces.
- Gravity
- Electromagnetic
- Strong
- Weak
What is gravity responsible for?
Attraction between objects that have mass.
What does the electromagnetic force do?
Responsible for attraction/repulsion between objects that have electric charge.
What is the strong force?
A short-range interaction occurring between objects made of quarks, holding protons and neutrons together.
What is the weak force?
A short-range interaction that occurs between elementary particles, weaker than electromagnetic or strong force.
What happens to gravitational force as the mass of interacting objects increases?
The force of attraction increases.
What happens to gravitational force as the distance between objects increases?
The force of attraction decreases.
How are gravitational forces mediated?
By gravitational fields, which require two or more objects.
What is the nature of gravitational forces?
Gravitational forces are always attractive.
What is an electrostatic force?
A special case of the electromagnetic force acting between charged particles.
How does the electromagnetic force compare to gravity?
The electromagnetic force is much stronger and can be both attractive and repulsive.
What is Coulomb’s Law used for?
To model the force between charged particles.
What are the two types of energy mentioned?
- Kinetic Energy
- Potential Energy
What is kinetic energy associated with?
Motion, calculated as KE = ½mv².
What is potential energy associated with?
The position of a system of objects in a field.
What is the law of conservation of energy?
The total energy remains constant; energy can be transferred or transformed but never lost.
What is the SI unit of energy?
Joule (kg m² s⁻²).
What is the relationship between potential energy and distance in a gravitational field?
Potential energy increases as the distance between the ball and Earth increases.
What causes potential energy to decrease when a ball falls?
The increase in kinetic energy.
