Unit 7 Lesson 2 Flashcards
(18 cards)
The number of (blank) always equals the number of (blank).
The number of protons always equals the number of electrons.
Describe the ways in which atoms make up matter.
-An atom is the smallest particle that an element can be divided into and still be the same element. An element is a substance that cannot be separated or broken down into simpler substances.
-Scientists now know that the atom is the smallest unit that has the chemical properties of an element.
What is an element?
A substance that cannot be separated or broken down into simpler substances by chemical means.
Describe scientific contributions to the atomic theory.
-Atomic theory was published.
-Electrons were discovered.
-Nucleus and protons were discovered.
-A model where electrons circle around the nucleus, with each path a certain distance from the nucleus was made.
-Neutrons were discovered.
What are isotopes?
Atoms of the same element that have different numbers of neutrons.
Keep going! I love you, and I’m so proud of you!
Think of how good that 100 is gonna feel! I see how hard you’re trying!
What are the four forces that work in an atom?
-Gravity
-Electromagnetic force
-The strong force (the force that keeps the protons close and is greater than the electromagnetic force)
-The weak force (the force that can change a neutron into a proton or electron)
What is the current atomic theory?
-Atoms are the basic unit of matter.
-Atoms of each element are unique.
-Atoms are made up of nucleus which contains protons and neutrons.
-Electrons move within the electron cloud.
What does chemistry focus on?
Chemistry focuses on the properties and reactions of matter; it all starts with the atom.
State the location, charge, and relative mass of protons, neutrons, and electrons in an atom.
Protons, Neutrons, Electrons
Charge I Mass (amu) I Location
Proton: +1 1 Nucleus
Neutron: 0 1 Nucleus
Electron: -1 0 Orbitals
Identify the nucleus and electron cloud in an atom.
Nucleus –> small circle in the middle of the atom
Electron cloud –> circles around the nucleus
Determine the atomic number and mass number of an atom.
Atomic number - Number of protons in the nucleus of an atom.
Mass number - The total number of protons and neutrons in an atom’s nucleus.
An atom can gain or lose electrons to become an ion, which has a net positive or negative charge.
Define atom.
The smallest particle in a unit of mass.
Define electron.
Negatively charged particles in the Orbitals.
Define nucleus.
A small, dense center that has a positive charge.
Define proton.
Positively charged particles in the nucleus.
Define neutron.
Uncharged particles in the nucleus.
Define electron cloud.
An area around the nucleus where electrons move.
