Chapter 2 Flashcards
Matter
Matter refers to anything that takes up space and has mass. Matter can exist as a solid, a liquid, or a gas.
Element
One of the basic building blocks of matter; an element cannot be broken down by chemical means. Each element has a name and a symbol. There are only 92 naturally occurring elements.
Why are elements arranged in a periodic table?
Elements in a column show periodicity, meaning that each column behaves similarly during chemical reactions.
Atom
The smallest unit of an element that still retains the chemical and physical properties of the element. It is the smallest unit to enter into chemical reactions.
What subatomic particles help make up an atom?
• Protons - positively charged
• Neutrons - uncharged
• Electrons - negatively charged
Protons and neutrons are located within the nucleus of an atom and electrons move about the nucleus.
Proton
Positive subatomic particle, located in the nucleus and having weight or approximately one atomic mass unit
Neutron
Neutral subatomic particle, located in the nucleus and having weight of approximately one atomic mass unit
Electron
Negative subatomic particle, moving about in an energy level around the nucleus of an atom
Electron shell
Average location, or energy level, of an electron in an atom
Atomic number
The number of protons within the nucleus of an atom.
Mass number
The sum of the number of protons and neutrons in the nucleus of an atom.
Atomic Mass
Mass of an atom equal to the number of protons plus the number of neutrons within the nucleus. It is the average of the atomic mass unit (AMU) for all the isotopes of that atom
Isotopes
Atoms with the same atomic number but a different atomic mass due to a different number of neutrons present in the nucleus
Radioisotope
An unstable form of an atom that spontaneously emits radiation in the form of radioactive particles or radiant energy.
Molecule
Union of two or more atoms of the same element; also, the smallest part of a compound that retains the properties of the compound
Compound
Substance having two or more different elements united chemically in a fixed ratio
What is an Ionic Bond?
Bonding between atoms in which electrons are exchanged to create a stable outer shell (for all atoms?)
Note: atoms with more than one shell are most stable when the outer shell has 8 electrons.
Ion
A charged particle that carries a negative or positive charge
Covalent Bond
Chemical bond in which atoms share one pair of electrons. The electrons spend part of their time in the outer shell of each atom so that both essentially have a stable outer shell.
What 4 main ingredients make up more than 90% human body?
Carbon, nitrogen, oxygen, and hydrogen
What are the two types of bonds between atoms?
- Ionic bond
* Covalent bond
