Forum

Shivani siva
@shivani-siva
Famed Member
Joined: Aug 6, 2021
Last seen: Sep 10, 2021
Topics: 289 / Replies: 1732
Reply
Reply
Answer to: Write the balanced equations for the following chemical reactions: (a) Hydrogen + Chlorine ➝ Hydrogen chloride

The balanced equations are written as: (a) H2 + Cl2 ➝ 2HCl (b) 3BaCl2 + Al2(SO4)3 ➝ 3BaSO4 + 2AlCl3 (c) 2Na + 2H2O ➝ 2NaOH + H2

4 years ago
Reply
Answer to: Why should magnesium ribbon be cleaned before burning in air?

Magnesium is a reactive metal. When it is exposed to atmosphere for longer time, the oxygen present in the atmosphere combines and MgO is formed on th...

4 years ago
Reply
Answer to: A metal salt MX when exposed to light splits up to form metal M and a gas X2. Metal M is used in making ornaments whereas gas X2 is used in making bleaching powder.

(a) Silver. (b) Chlorine. (c) Silver chloride. (d) Silver nitrate and Sodium chloride. (e) Decomposition reaction; 2AgCl(s) + Light + Decomp...

4 years ago
Reply
Answer to: A red-brown metal X forms a salt XSO4. When hydrogen sulphide gas is passed through an aqueous solution of XSO4, then a black precipitate of XS is formed along with sulphuric acid solution.

(a) Copper sulphate. (b) Blue colour. (c) Copper sulphide. (d) CuSO4 (aq) + H2S(g) → CuS (s) + H2SO4 (aq) (e) Double displacement reaction.

4 years ago
Reply
Answer to: Two metals X and Y form the salts XSO4 and Y2SO4, respectively. The solution of salt XSO4 is blue in colour whereas that of Y2SO4 is colourless.

(a) Metal X : Copper; Metal Y : Sodium (b) Copper sulphate, CuSO4 (c) Sodium sulphate, Na2SO4 (d) Barium sulphate, BaSO4 (e) Copper chloride, ...

4 years ago
Reply
Answer to: A metal X forms a water soluble salt XNO3. When an aqueous solution of XNO3 is added to common salt solution, then a white precipitate of compound Y is formed along with sodium nitrate solution.

(a) Silver (Ag) (b) Silver nitrate (AgNO3) (c) Silver chloride (AgCl) (d) AgNO3(aq) + NaCl (aq) → AgCl (s) + NaNO3 (aq) (e) Double displacemen...

4 years ago
Reply
Answer to: When a black metal compound XO is heated with a colourless gas Y2, then metal X and another compound Y2O are formed. Metal X is red-brown in colour which does not react with dilute acids at all.

(a) Copper (Cu) (b) Hydrogen (H2) (c) Copper oxide (CuO) (d) Water (H2O) (e) CuO + H2 → Cu + H2O (f) Displacement reaction (which is also a ...

4 years ago
Reply
Answer to: A strip of metal X is dipped in a blue coloured salt solution YSO4. After some time, a layer of metal Y from the salt solution is formed on the surface of metal strip X.

(a) Metal X is Zinc (Zn). (b) Metal Y is Copper (Cu). (c) The metal salt YSO4​ is Copper sulphate (CuSO4) (d) Displacement reaction; CuSO4 (a...

4 years ago
Reply
Answer to: A colourless lead salt, when heated, produces a yellow residue and brown fumes.

(a) Lead nitrate. (b) Nitrogen dioxide. (c) 2Pb(NO3)2 + Heat + Decomposition → 2PbO(s) + 4NO2 (g) + O2 Lead Nitrate Lead monoxide Nitrogen D...

4 years ago
Reply
Answer to: What happens when an aqueous solution of sodium sulphate reacts with an aqueous solution of barium chloride? (b) Write the balanced chemical equation for the reaction which takes place.

(a) When barium chloride solution is added to sodium sulphate solution, then a white precipitate of barium sulphate is formed along with sodium chlori...

4 years ago
Reply
Answer to: Explain the term “rancidity”. What damage is caused by rancidity? (b) What type of chemical reaction is responsible for causing rancidity?

(a) The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called rancidity. It spoils the food ...

4 years ago
Reply
Answer to: Explain the term “corrosion” with an example. Write a chemical equation to show the process of corrosion of iron. (b) What special name is given to the corrosion of iron?

(a) Corrosion is the process in which metals are eaten up gradually by the action of air, moisture or a chemical (such as an acid) on their surface. R...

4 years ago
Reply
Answer to: What happens when a zinc strip is dipped into a copper sulphate solution?

When a strip of zinc metal is placed in copper sulphate solution, then zinc sulphate solution and copper are obtained. (a) CuSO4(aq) + Zn → ZnSO4 + ...

4 years ago
Reply
Answer to: What happens when silver chloride is exposed to sunlight? Write a chemical equation for this reaction. Also give one use of such a reaction.

When silver chloride is exposed to light, it decomposes to form silver metal and chlorine gas. 2AgCl(s) + Light + Decomposition → 2Ag(s) + Cl2(g) ...

4 years ago
Reply
Answer to: What happens when silver nitrate solution is added to sodium chloride solution? (a) Write the equation for the reaction which takes place. (b) Name the type of reaction involved.

When silver nitrate solution is added to sodium chloride solution, then a white precipitate of silver chloride is formed along with sodium nitrate sol...

4 years ago
Page 21 / 102

How Can We Help?