Chemistry
State the information provided by a chemical equation. Chemical equations suffer from a number of limitations. State the main limitations of a chemical equation.
Answer
Information provided by a chemical equation :
- The formulas & symbols of the reactants & products.
- The physical state of the substance whether it is solid, liquid or gas.
- The special conditions required such as heat, catalyst, direction of reaction.
- Tells the ratio in which the substances react in a balanced equation.
Chemical equation do not tell us about:
- The physical states of the reactants & products - hence [(s) for solids, (g) for gas may be added]
- The conditions such as temperature, pressure or catalyst which affect the reaction.
- The concentration of the reactants & products hence [(dil.) dilute & (conc) concentrated may be added.]
- The nature of the chemical reaction.
- The speed of the reaction.
- The heat changes accompanying the reaction.
- The completion of the reaction.
Related Questions
Write the chemical formula of Iron [III] oxide in a step-by-step manner.
What is a chemical equation. How it is represented. Differentiate between a 'word equation' and a 'molecular equation' with a suitable example.
State what is a balanced equation with a relevant example. Give a reason why an equation is balanced with reference to the law of conservation of matter.
Write balanced molecular equations for the following word equations:
(a) Calcium + oxygen ⟶ Calcium oxide
(b) Calcium + water ⟶ Calcium hydroxide + hydrogen
(c) Zinc + sulphuric acid ⟶ Zinc sulphate + hydrogen
(d) Lead sulphate + ammonium hydroxide ⟶ Ammonium sulphate + lead hydroxide
(e) Copper hydroxide + nitric acid ⟶ copper nitrate + water
(f) Lead nitrate + sodium chloride ⟶ sodium nitrate + lead chloride