मराठी
सी.आई.एस.सी.ई.आयसीएसई ICSE Class 7

Define chemical reaction.

Advertisements
Advertisements

प्रश्न

Define chemical reaction.

व्याख्या
Advertisements

उत्तर

Any chemical change in matter that involves its transformation into one or more new substances is called a chemical reaction.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 5: Language of Chemistry - Exercise

APPEARS IN

सेलिना Concise Chemistry [English] Class 7 ICSE
पाठ 5 Language of Chemistry
Exercise | Q 1.1
सेलिना Concise Chemistry [English] Class 7 ICSE
पाठ 5 Language of Chemistry
Additional questions | Q 1.1

संबंधित प्रश्‍न

Complete and balance the following chemical equations:

`"H"_2"S"` + `"CI"_2`  `→`  


Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.

\[\ce{NH3_{(g)} + HCl_{(g)} -> NH4Cl_{(s)}}\]


What are chemical reactions?


Define electrolysis.


Name the type of chemical reaction shown by the following equation:

2Mg + O2 → 2MgO


Name the type of chemical reaction shown by the following equation:

NaOH + HCl → NaCl + H2O


Reactants Products Type of chemical reaction
BaCl2(aq) + ZnSO4(aq) H2CO3(aq) Displacement
2AgCl(s) FeSO4(aq) + Cu(s) Combination
CuSO4(aq) + Fe(s) BaSO4↓ + ZnCl2(aq) Decomposition
H2O(l) + CO2(g) 2Ag(s) + Cl2(g) Double displacement

Give an example of the following chemical change.

A reaction where colour change is noticed


State the type of reactions for the following represent and balance the ones that are not balanced.

Cl2 + 2KBr → 2KCl + Br2 


Name the gases which turn moist red litmus blue.


Explain the term ‘chemical reaction’ with special reference to – ‘reactants’ and ‘products’.


Name the following:

The products obtained during ‘photosynthesis’ – which is a chemical change.


Give balanced equation for the following conversion affected by heat alone on the substance:

Copper carbonate to copper oxide


Give balanced equation for the following conversion affected by heat alone on the substance:

Copper nitrate to nitrogen dioxide


Match the chemical reactions in List I with the appropriate answer in List II.

  List I   List II
1. \[\ce{XY⇌[heat]X + Y}\] A: Displacement reaction
2. \[\ce{XY->X + Y}\] B: Double decomposition
3. \[\ce{X+Y- + A+B^-->X+B- + A+Y-}\] C: Endothermic reaction
4. \[\ce{X + YZ->XZ + Y}\] D: Thermal dissociation
5. \[\ce{X + Y->[heat]XY -\Delta}\] E: Decomposition reaction

A chemical reaction is often accompanied by external indications or characteristics.


What kind of a change is associated with decaying of a plants?


Discuss how acid rain occurs due to emission of smoke from vehicles and industries?


If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.

Can you change rust back into iron by some simple method?


Photosynthesis is a chemical charge. Justify your answer.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×