chemical reactions Flashcards
(23 cards)
what change is irreversible?
chemical
what is a reversible change called?
physical
what do we see during a physical change?
change of state. melting,freezing evaporation, condensation
what happens during a chemical change?
fizzing,change in colour or tempreature
combustion is…..
burning
what is the equation for combustion?
metal + oxygen —> metal oxide
combustion is an example of what?
an oxidation reaction
what is the definition of a fuel?
a substance that is burned to give out heat energy.
what is the test for oxygen?
if oxygen is present in a test tube a glowing splint will relight if held inside.
what is the test for hydrogen?
if hydrogen is present in a test tube a squeaky pop will sound when a light splint is held inside.
what is the metal and metal equation?
acid + metal —> salt + hydrogen
what acid creates a chloride salt?
hydrochloric acid
what salt does sulfric acid create?
sulfate
what acid makes a nitrate salt?
nitric acid
what is thermal decomposition?
when substances break down to simpler products when thay are heated
what is the equation for thermal decomposition?
metal crabonate —-> metal oxide + carbon dioxide
carbon dioxide is created when …
metal carbonates decompose
what do you do to test a gas to see if it is carbon dioxide?
it is bubbled through to lime water and if the lime water turns cloudy it is carbon dioxide.
what is electrolysis ?
a process where compounds are decomposed
define an exothermic reaction is?
when energy is given out. results in a rise in tempreture t
what is an endothermic reaction?
energy is take in. resulting in a fall in tempreature
when it ends in -ide it ….
it only has that element
when it ends in -ate it ……
it contains that element and oxygen.
