Chemical reactions and equations Unit 6

Diatomic elements

7 pure elements that exist as pairs in nature — the only pure covalent bonds

How to remember the covalent bonds?

BRINCLEHOF

Conservation of matter

In all chemical and physical changes, matter is neither created or destroyed

The total mass in a chemical reaction remains _______

constant

Chemical Reaction

process in which a new substance with different physical and chemical properties is produced

Reactants

The substance you start with

Products

The substance you end up with

In a chemical reaction…

Atoms are rearranged into new molecules

Arrow

Separates the reactant from the product

(aq)

aqueous solution, dissolved in water

double arrow

indicates a reversible reaction

Can have heat on top of arrow as well

Shows that heat is supplied to the reaction

Any element over arrow

Indicates that a catalyst is supplied

Catalyst

a substance that speeds up a chemical reaction

valence electrons

their arrangement determines whether or not an atom will bond

energy

needed to initiate a chemical reaction

Synthesis

Decomposition

Single replacements

Double replacement

Has h20 and c02