reactivity series

when metal reacts with cold water

metal hydroxide + hydrogen

K, Na, Ca, Mg

when metal reacts with steam

metal oxide + hydrogen

[K, Na, Ca] Mg, Zn, Fe

when metal reacts with dilute hydrochloric acid

metal chloride + hydrogen

[K, Na] Ca, Mg, Zn, Fe

what is a displacement reaction?

• a more reactive metals pure metals can displace a less reactive metal from its salt solution

• more reactive become ion

• less reactive become elements

which metals are extracted by electrolysis? why

K, Na, Carbon, Mg, Al. they are very reactive, compounds are very difficult to break down

what metals are extracted by carbon? why

Zn, Fe, Pb, Cu. they are less reactive. reduce their oxides with carbon

what is rust and what causes rusting?

rust is exceedingly flaky and brittle.

when iron or steel reacts with oxygen and water.

steel: iron + carbon

name and formula of rust

hydrated iron (III) oxide

Fe2O3 . xH2O

what affects the rate of rust?

neutral substance: sodium chloride

acidic substances: carbon dioxide, sulfur dioxide

how to prevent rusting? what are the methods

using a protective layer

• painting

• oiling

• plastic coating

• tin plating

• chrome plating