Last seen: Sep 10, 2021
Aqueous solution of an acid releases H+ and H3O+ in solution. Since ions are carriers of charge, therefore they are responsible for conducting electri...
All the listed acids have replaceable hydrogen atoms which they release in aqueous solution as hydrogen ions. Therefore, they show acidic character. H...
The gas evolved with effervescence and extinguishes a lit candle is CO2. If one of the compounds formed is CaCl2, the reaction would be CaCO3(s) + H...
Metals are mostly reactive in nature. They react with dilute acids (HCl and H2SO4) to evolve hydrogen gas. For example: Zn(s) + 2HCl(aq) ➝ ZnCl2(...
Both curd and other sour substances contain some acids in them. They react with copper or brass vessels to form certain salts which are not good for h...
Take a small volume of all three liquids in three different test tubes. Dip red litmus paper strips separately in all the three test tubes. The tube i...
(a) Corrosion is a chemical process of decay of metal when they are exposed to moisture. (b) Rusting Corrosion of iron is called rusting. It is a s...
Oil and fat containing food items or eatables get rancid due to oxidation by air or oxygen. In case the container or bag is flushed with nitrogen, the...
Iron is a reactive metal. In the presence of humid air (O2 + H2O), it rusts to form a layer of Fe2O3.xH2O. To prevent it from rusting, paint is appl...
The element ‘X’ is copper and the black- coloured compound formed is copper(II) oxide. 2CuO + O2(g) ➝ 2CuO (X) (Black)
(a) Oxidation involves the gain of oxygen by a substance in a chemical reaction. Examples: 2Zn(s) + O2(g) + Heat ➝ 2ZnO(s) 2Ca(s) + O2(g) + Heat...
In a precipitation reaction, one of the products formed during the reaction does not dissolve in solution and gets settled on the surface of the conta...
The chemical equation for the displacement reaction is: AgNO3(aq) + NaCl(aq) ➝ AgCl(s) + NaNO3(aq) BaCl2(aq) + Na2SO4(aq) ➝ BaSO4(s) + 2NaCl(aq)
In a displacement reaction, one element takes the place of another in a compound. For example, Fe(s) + CuSO4(aq) ➝ FeSO4(aq) + Cu(s) In a doubl...
(a) MgCO3 + Heat ➝ MgO + CO2(g) (b) 2AgCl + Light ➝ 2Ag + Cl2 (c) 2NaCl + Electricity ➝ 2Na + Cl2
Decomposition reactions are called the opposite of combination reactions because of the following: In decomposition reactions, larger molecules br...
Respiration is a biochemical reaction which releases energy during combustion of digested food (glucose) in the cell producing carbon dioxide and wate...
A chemical reaction in which certain amount of heat energy is evolved and resulting contents get heated up is called exothermic reaction. Examples: ...
(a) 2KBr(aq) + BaI2(aq) ➝ 2KI(aq) + BaBr2(aq) The reaction is known as double dis-placement reaction. (b) ZnCO3(s) ➝ ZnO(s) + CO2(g) The reactio...
All these equations are in word form whereas the balanced equations are written in symbolic form. (a) Ca(OH)2 + CO2 ➝ CaCO3 + H2O (b) 2Al + 3CuCl2...