2.1 Constituents of the atom

• What is the smallest unit of matter that retains the chemical properties of an element?

  Atom
• Which subatomic particle forms chemical bonds?

  Electron
• Electrons have a mass approximately equal to zero atomic mass units (amu).


  True
• Neutrons in the nucleus contribute to its stability
• Electrons are located within the nucleus of an atom.

  False
• Order the subatomic particles by their charge from most positive to most negative:

  1️⃣ Proton

  2️⃣ Neutron

  3️⃣ Electron
• What is the charge of a proton?

  +1
• Protons determine the element's identity


  True
• Neutrons stabilize the nucleus by adding mass without affecting its charge.


  True
• Match the subatomic particle with its property:

  Proton ↔️ +1 charge

  Neutron ↔️ 0 charge

  Electron ↔️ -1 charge
• What is the central, dense part of an atom called?

  Nucleus
• Match the subatomic particle with its primary function:

  Proton ↔️ Determines element's identity

  Neutron ↔️ Stabilizes nucleus

  Electron ↔️ Forms chemical bonds
• Electrons orbit the nucleus in specific energy levels.
• The mass of an electron is negligible compared to protons and neutrons.


  True
• Where are protons located in an atom?

  Nucleus
• Electrons have a negative charge of -1 and a negligible mass compared to protons and neutrons.
• Protons have a charge of +1 and a mass of 1 amu.
• What does the nuclear model describe an atom as having?

  Dense nucleus with electrons
• Electrons orbit the nucleus in specific energy levels


  True
• Order the steps in the process of ion formation

  1️⃣ Atom gains or loses electrons

  2️⃣ Atom becomes positively or negatively charged
• Electrons have a mass of approximately 0 atomic mass units (amu).
• Which subatomic particle has a positive charge and is located in the nucleus?

  Proton
• What is the charge and mass of a proton?

  +1 charge, 1 amu mass
• The nucleus of an atom contains positively charged protons and neutral neutrons.


  True
• The nucleus of an atom contains nearly all of its mass but occupies only a tiny fraction of its volume.

  True
• Ions are atoms that have gained or lost electrons
• What role do protons play in chemical reactions?

  Determine atomic number
• What is the primary role of electrons in chemical reactions?

  Form chemical bonds
• Protons, which have a positive charge, are located in the nucleus
• The number of protons in an atom determines its identity
• Order the subatomic particles by their mass from heaviest to lightest:

  1️⃣ Proton

  2️⃣ Neutron

  3️⃣ Electron
• What does the nuclear model of the atom describe?

  Dense nucleus with orbiting electrons
• Match the subatomic particle with its properties:

  Proton ↔️ +1 charge, 1 amu

  Neutron ↔️ 0 charge, 1 amu

  Electron ↔️ -1 charge, approximately 0 amu
• Protons have a mass of 1 atomic mass unit (amu).
• What is the charge of a neutron?

  0
• The differences between subatomic particles include their charge, mass, location, and function

  True
• Match the subatomic particle with its properties:

  Proton ↔️ Positive charge, nucleus

  Neutron ↔️ Neutral charge, nucleus

  Electron ↔️ Negative charge, orbits nucleus
• What houses almost all of the atom's mass according to the nuclear model?

  Nucleus
• What is the charge of an ion?

  Positive or negative
• What is the approximate mass of a proton in atomic mass units (amu)?

  1