unit 2 topic 8 Flashcards
how can higher temperatures change the rate of a chemical reaction?
it increases, faster-moving molecules and atoms collide more frequently and therefore they can form new substances more quickly
- for example, fresh fruit are put into the refrigerator ro slow down the chemical reaction.
how can stirring and surface area change the rate of reactions
stirring will speed up the reaction rate because it will change the size or the concentration of the reactants. If you grind up the object there will be more surface area for a chemical reaction.
a catalyst increases only the ___ of the reaction
SPEED
what is enzyme
is a natureal catalyst made by living things.
almost all enzyme take place where?
in our body
what is an example of enzyme?
when you eat a piece of bread our mouth glands will produce saliva which will contain enzyme and the saliva will act as a catalyst to help break down the food into smaller molecules
what does a contalyst not affect
the amount of the product produced in a chemical reaction
what are inhibitors
they are substances that slow down chemical reactions
what is an example fo inhibitors are used
some foods and medicines use it to slow down their decomposition
what happend to some metals when they are exposed to air and moisture?
the metals undergo a chemical reaction and gradually corrode
what is the formual for iron oxude or (Rust)
4Fe + 30₂ → 2Fe₂O₃ (Iron oxide)
Iron). (oxygen
how does corrotion affect metals
corroded materials lose their stregth. Once the top layer of metal has corroded, more surface area is exposed meaning that oxygen from the air can reach the inner layers. This will eventually make rust.
how can you protect a metal from corrosion
to apply a thin layer of paint, or coat it with zinc which is more resistant to corrosion
the process of coating metals with a thinlayer of zinc is called what?
galvanization
