Quantum theory describes the behavior of particles at the _______ level.

Answer explanation

Quantum theory describes the behavior of particles at the atomic and subatomic level, focusing on the fundamental aspects of matter and energy that govern their interactions.

Tags

NGSS.HS-PS4-3

Which of the following is a fundamental concept of quantum theory?

• A) Wave-particle duality

• B) Classical mechanics

• C) Newton's laws

• D) Thermodynamics

Answer explanation

Wave-particle duality is a fundamental concept of quantum theory, describing how particles like electrons exhibit both wave-like and particle-like properties. This contrasts with classical mechanics, which does not account for this duality.

Tags

NGSS.HS-PS4-3

Match the following concepts with their descriptions.

• Quantum Entanglement

• Particles are interconnected regardless of distance

• Quantum Superposition

• Particles can exist in multiple states at once

• Heisenberg Uncertainty Principle

• The position and momentum of a particle cannot both be precisely measured.

What is the smallest particle of an element that retains all the properties of that element?

• Molecule

• Atom

• Electron

• Neutron

Answer explanation

The smallest particle of an element that retains all its properties is the atom. Atoms consist of protons, neutrons, and electrons, and they define the chemical identity of an element, unlike molecules or subatomic particles.

What is the term for the lowest energy state of an atom?

• Excited state

• Ground state

• Quantum state

• Atomic state

Answer explanation

The lowest energy state of an atom is called the ground state. In this state, the electrons are in their closest orbits to the nucleus, minimizing energy. Excited states occur when electrons absorb energy and move to higher orbits.

Explain how the wavelike properties of electrons relate to atomic emission spectra, energy states of atoms, and atomic orbitals.

Answer explanation

Electrons exhibit wavelike properties, leading to quantized energy states in atoms. When electrons transition between these states, they emit or absorb specific wavelengths of light, creating atomic emission spectra that correspond to atomic orbitals.

Tags

NGSS.HS-PS4-1

NGSS.HS-PS4-3

The (a)   mechanical model of the atom describes the behavior of electrons in atoms.

• Classical

• Quantum

• Newtonian

• Relativistic

Answer explanation

The quantum mechanical model of the atom accurately describes electron behavior, incorporating principles of wave-particle duality and uncertainty, unlike classical or Newtonian models which cannot account for these phenomena.

The (a)   uncertainty principle states that it is impossible to know both the velocity and the position of a particle at the same time.

• Einstein

• Heisenberg

• Bohr

• Schrödinger

Answer explanation

The Heisenberg uncertainty principle asserts that the more precisely we know a particle's position, the less precisely we can know its velocity, and vice versa. This principle is fundamental in quantum mechanics.

Fill in the blank: The lowest allowable energy state of an atom is called its _________.

Answer explanation

The lowest allowable energy state of an atom is called its ground state. In this state, the atom is at its most stable configuration, with electrons occupying the lowest energy levels available.

Explain what happens when an atom gains energy according to Bohr's model.

Answer explanation

When an atom gains energy, it can move to a higher energy level or orbit, as described by Bohr's model. This process is called excitation, and when the atom returns to a lower energy level, it releases energy, often as light.