Chemistry Flashcards
What is the basic unit of matter?
Atom
True or False: A molecule is made up of two or more atoms bonded together.
True
Fill in the blank: The __________ is the center of an atom and contains protons and neutrons.
nucleus
What are the three subatomic particles?
Protons, neutrons, and electrons
Which particle has a positive charge?
Proton
What is the charge of an electron?
Negative
What is the atomic number of an element?
The number of protons in the nucleus of an atom.
True or False: The mass number is the sum of protons and electrons in an atom.
False
What is an isotope?
Atoms of the same element with different numbers of neutrons.
What do we call a substance made of only one type of atom?
Element
Fill in the blank: A __________ is a combination of two or more elements that are chemically bonded.
compound
What is the periodic table?
A table that organizes all known elements by their atomic number.
Which group of the periodic table contains noble gases?
Group 18
What is the main characteristic of metals?
They are good conductors of heat and electricity.
True or False: Nonmetals are typically brittle and poor conductors.
True
What is a chemical reaction?
A process that involves the rearrangement of atoms to form new substances.
What do we call the starting materials in a chemical reaction?
Reactants
What is produced in a chemical reaction?
Products
Fill in the blank: The law of conservation of mass states that mass is neither __________ nor __________ in a chemical reaction.
created, destroyed
What is an acid?
A substance that donates protons (H+) in a chemical reaction.
What is a base?
A substance that accepts protons (H+) in a chemical reaction.
True or False: Acids taste bitter.
False
What is pH a measure of?
The acidity or basicity of a solution.
What is the pH of neutral solutions?
7
