Download App

Language of Chemistry — CHEMISTRY STD 8 — Question

ICSE BoardEnglish MediumSTD 8CHEMISTRYLanguage of Chemistry4 Marks
Question
What is a chemical equation. How is it represented. Differentiate between a 'word equation' and a 'molecular equation' with a suitable example.
✓

Answer

“Chemical equation is a short form $–$ representing the result of a chemical change.”
OR
“Is the representation of a chemical change.”
Word equation tells which substances react $($take part$)$ in chemical reaction and which substances are produced where as molecular equation symbols and molecular formulas are used for both reactants and products.
Example :
When zinc reacts with dilute sulphuric acid, both being reactants, products produced are zinc sulphate and hydrogen gas, which are shown as below :
Word equation :
Zinc $+$ Sulphuric acid $\rightarrow$ Zinc sulphate $+$ Hydrogen
Molecular equation :
$\underset{\text { Zinc }}{ Zn }+\underset{\text { [Sulphuric acid] }}{ H _2 SO _4 \text { (dil.) }} \longrightarrow \underset{\text { [Zinc sulphate] }}{ ZnSO _4}+\underset{\text { [Hydrogen] }}{ H _2[ g ]}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "[5 Mark Question Answer]" from Language of Chemistry→Language of Chemistry — all question types→CHEMISTRY STD 8 question papers→ICSE Board STD 8 question papers→ICSE Board question paper generator→

Similar questions

What are $(i)$ positive catalysts and $(ii)$ negative catalysts? Support your answer with one example for each of them.
→
State four differences between compounds and mixtures.
→
What is meant by the metal reactivity series ? State its importance, $($any two points$)$.
→
Differentiate between :
Desirable and undesirable change
→
State which of the three states of matter Le. solids, liquids or gases $–$ have
$(a)$ No definite volume
$(b)$ A definite shape
$(c)$ High density
$(d)$ No free surfaces
$(e)$ Particles $–$ which diffuse very easily.
→
What are the main causes of water pollution ? How can it be controlled ?
→
State what is meant by ‘reactivity series of metals’. With reference to $- (a)$ Water $(b)$ Acids explain with suitable examples how the reactivity of the metals could be differentiated.
→
Match the statements in Column $A$ with those in Column $B.$
Column $A$ Column $B$
$1.$ A metal which reacts with cold water to from hydrogen. $1.$ Reduction
$2.$ A gas which is inflammable and non$-$supporter of combustion $2.$ Hydrogenation
$3.$ A process in which vanspati ghee is prepared from vegitable oils $3.$ oxidation
$4.$ The removal ofhydrogen or addition of oxygen $4.$ sodium
$5.$ The addition of hydrogen or removal of oxygen $5.$ Hydrogen
→
Differentiate between :
Slow and Fast changes
→
With reference to the discovery of the structure of an atom, explain in brief $-$ William Crookes experiment for the discovery of cathode rays, followed by $-$ J.J. Thomsons experiment pertaining to the constituents of the cathode rays. State which sub$-$atomic particle was discovered from his experiment.
→