Predicting Metal Reactions

What is the general rule?

What is the general rule?

Metal reactivity increases to the bottom left of the periodic table, with Francium (Fr) being the most reactive.

Metal reactivity:

• Metals with the first low ionisation energy are more reactive, meaning that metals in Group 1 metals are the most reactive.

• Transition metals have larger nuclear attraction and are generally less reactive.

Metal + Water → Metal oxide/Metal hydroxide + Hydrogen Gas

• K, Na, CL → reacts with cold water

• Mg → reacts with hot water

• Al, Zn, Fe → reacts with steam when red hot

• Pb, Sn, Cu,Hg, Ag, Au → no reaction

Water & metal reactivity

• Water of higher temperatures provide more energy to ionise metals allowing for reaction, with lower element groups being more reactive.

• Water temperature for reaction helps predict metal reactivity

Metal + dilute acid → salt + hydrogen gas

• K, Na, Ca → bubbles rapidly and hydrogen gas formed may spontaneously combust

• Mg → bubbles rapidly & releases hydrogen

• Al, Zn, Fe → Bubbles very slowly to moderately, reacts faster in warm acid

• Pb, Sn, Cu, Hg, Ag, Au → no reaction

Metal + oxide → metal oxide

• K, Na, Ca → burn rapidly to form oxides or peroxides, combusts spontaneously in air

• Mg → Burn readily of powders or as fine fibres to form oxides

• Al, Zn, Fe, Pb, Sn, Cu, Hg → becomes coated with oxide layers which prevent further oxidisation

• Ag, Au → no reaction

Metal and metal ions

• Less reactive metal solutions ionise more reactive metals

• Less reactive metal ions deposit out of solution