Questions and Answers
What type of electrons are responsible for controlling the chemical properties of an element?
Valence electrons
What is the atomic number of the element with the electron configuration 1s2 2s2 2p2?
6
Why are filled shells more stable than unfilled shells?
Because filled shells have a full octet of electrons, which is a more stable arrangement.
What is the name of the electron shell with n = 4 in the electron configuration of Fe (atomic number = 26)?
Signup and view all the answers
What is the significance of the valence electrons in an atom?
Signup and view all the answers
How many valence electrons are present in the electron configuration of Fe (atomic number = 26)?
Signup and view all the answers
What is the primary reason why the electron configuration of most elements is not stable?
Signup and view all the answers
What is the atomic number of the element with the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6?
Signup and view all the answers
What is the relationship between the number of electrons in the valence shell and the chemical properties of an element?
Signup and view all the answers
What is the electron configuration of the element with atomic number 11?
Signup and view all the answers
How do the electron shells of an atom relate to its bonding behavior?
Signup and view all the answers
What is the characteristic of the electron configuration of noble gases, such as Neon and Argon?
Signup and view all the answers
What determines the atomic number of an atom?
Signup and view all the answers
What is the unit of measurement for atomic mass?
Signup and view all the answers
What properties of an element are determined by its electronic structure?
Signup and view all the answers
What are the three quantum numbers that describe an electron's energy state?
Signup and view all the answers
What is the tendency of electrons in energy states?
Signup and view all the answers
What is the relationship between the atomic number and the number of electrons in a neutral atom?
Signup and view all the answers
What is the significance of valence electrons in bonding?
Signup and view all the answers
Why do electrons occupy specific energy states?
Signup and view all the answers
Study Notes
Electron Configurations
- Valence electrons are those in unfilled shells and are most available for bonding, controlling chemical properties.
- Example: Carbon (atomic number 6) has an electron configuration of 1s2 2s2 2p2, with valence electrons in the 2p orbital.
Iron (Fe) Electron Configuration
- Fe has an atomic number of 26, with an electron configuration of 1s2 2s2 2p6 3s2 3p6 3d6 4s2.
- The electron configuration can be represented in a diagram showing the energy levels and orbitals.
Survey of Elements
- Most elements do not have a stable electron configuration.
- Examples of electron configurations for various elements are:
- Hydrogen (H): 1s1
- Helium (He): 1s2 (stable)
- Lithium (Li): 1s2 2s1
- Beryllium (Be): 1s2 2s2
- Boron (B): 1s2 2s2 2p1
- Carbon (C): 1s2 2s2 2p2
- ...Neon (Ne): 1s2 2s2 2p6 (stable)
Atomic Structure
- An atom consists of electrons, protons, and neutrons.
- Atomic number is the number of protons in the nucleus, equal to the number of electrons in a neutral species.
- Atomic mass unit (amu) is 1/12 the mass of a 12C atom, and atomic weight is the weight of 6.022 x 10^23 molecules or atoms.
Properties Determined by Electronic Structure
- Four properties determined by electronic structure are:
- Chemical properties
- Electrical properties
- Thermal properties
- Optical properties
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
