Chemistry Flashcards
What is the atomic number of an atom?
The number of protons an atom has
What is the atomic mass or mass number of an atom?
The number of protons and neutrons an atom has
What is an ion?
An atom ore molecule that has gained or lost one or more of their valence electrons and therefore have a net positive or negative charge
What is an atom?
An incredibly small particle made of mostly empty space
What is an element?
A unique, pure chemical substance made of atoms of only one type
What is an isotope?
An atom with the same number of protons, but different numbers of neutrons
What does a compound contain?
Atoms of different elements chemically bonded together
What is a mixture made of?
Two or more substances that are not chemically combined
What does the Law of Conservation of mass state?
During chemical reactions, matter is neither created or destroyed
What is the main rule during all chemical reactions?
The total mass of products is always equal to the total mass of reactants
What are molecules?
Small groups of atoms chemically bonded together
What are the signs of a chemical reaction occurring?
Change in colour, change in temperature, formation of a precipitate, emission of light or production of gas
What are the columns of the periodic table known as?
Groups
What are the rows of the periodic table known as?
Periods
What do all elements in the same group contain?
Similar chemical properties and the same number of outer shell electrons
