Type of chemical reactions

Chemical reaction:

Substances known as reactants disappear over time to be replaced by chemical different substance known as a product → total mass and number of each type of atom present is unchanged but the way they are arranged/bonded is different

Describe common types of chemical reactions.

synthesis reaction Two or more simple substances combine to forma more complex product

• A + B → AB
  

Decompotion reaction Single bond breaks down into two to more simpler substances

• AB→A + B

Single replacement one elemnt replaces another element in a compound

• A+ BC → AC + B

Double replacement Ions of twop compounds exchange places in aqueous solution to form two new compounds

• AB+ AC → AD +CB

List the products of chemical reactions.

Decomposition of Metal carbonate by heating - when metal carbonate reacts with acid it forms a salt, water and gaseous Carbon dioxide

General chemical equation: MCO_3(s) → MO_(s) + CO_2(g)

Example: CaCO_3(s) → CaO_(s) + CO_2(g)

Decomposition of a Metal carbonate acid - when metal carbonate reacts with an acid, it forms a salt, water and gaseous Carbon dixoide

chemical equation:

• MCO_3(s) + acid_(aq) → salt_(aq) + H₂O_(l) + CO_2(g)

Example:

• CaCO_3(s) + HNO_3(aq) → Ca(NO₃)_2(aq) + H₂O_(l) + CO_2(g)

Oxidation of a Metal - metal reacts with oxygen → outer layer of a piece of metal will appear matted and dulll once its oxidised

General chemical equation

• 2M + O₂ → 2MO

Example:

• 2Mg_(s) + O_2(g) → 2MgO_(s)
  

Reaction of a reactive Metal with an acid - reactve metal reacts with an acid to form a salt and hydrogen gas → causes vigorous bubbling

General chemical equation

• M + acid → salt + H₂

Example:

• Al_(s) + 2HCl_(aq) → AlCl_3(aq) + H_2(g)

Aqueous solution mixture where particles of solute are homogeneously spread amongst particles of solvent

• When solvent is used with water we call these solutions aqueous solution

• we don’t need to include water in the equation as water doesn’t take part

• Products of a reaction will either dissolve or precipitate based on solutbility

Precipitation reactions two aqueous solutions react to form an insoluble (precipitate) and soluble compound

General chemical equation

• AB_(aq) + CD_(aq) → AD_(s) + CB_(aq)

Example:

• AgNO_3(aq) + NaCl_(aq) → AgCl_(s) + NaNO_3(aq)

Metal displacement reactions - A more reactive metal displaces a less reactive metal from its compound

• A A + BC → AC + B

• Zn_(s) + CuSO_4(aq) → ZnSO4_(aq) + Cu_(s)

Halogen displacement reactions - a more reactive halogen displacesless reactive halogen from its compound

General chemical equations:

• X + YZ → YX + Z

Example:

Cl_2(g) + 2KBr_(aq) → 2KCl_(aq) + Br_2(l)

Neutralisation reactions ( acid and base) - an acid reacts with a base to form a salt and water

Chemical equation

• Acid + Base → salt + water

Example:

• HCl + NaOH → NaCl + H₂O

Universal indicator strong acids are red,Neutral green, Strong bases are purple

Write simple chemical equations of each chemical reaction