Ch5.2 Flashcards
(7 cards)
What is a compound?
A substance made of two or more elements chemically combined in a fixed ratio.
How does a compound differ from a mixture?
Compounds can’t be separated by physical means, only by chemical changes. Mixtures can be separated physically.
What is an example of a compound with a fixed ratio?
Methane (CH₄), which always has 4 hydrogen atoms for every 1 carbon atom.
What is a chemical change?
A change that produces matter with a different composition, such as breaking down a compound.
How can water be broken into hydrogen and oxygen?
By passing an electric current through it (electrolysis), not by heating.
How does the compound sodium chloride (NaCl) compare to its elements?
Sodium is a reactive metal, chlorine is a poisonous gas, but together they form table salt, a stable and safe compound.
Why are compound properties important in chemistry?
Because compounds often have completely different properties than the elements that form them.
