Question
An element X which is a yellow solid at room temperature shows catenation and allotropy. X forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and are the major air pollutants.
  1. Identify the element X.
  2. Write the electronic configuration of X.
  3. Write the balanced chemical equation for the thermal decomposition of ferrous sulphate crystals?
  4. What would be the nature (acidic/ basic) of oxides formed?
  5. Locate the position of the element in the Modern Periodic Table.

Answer

  1. The available information suggests that the element X is sulphur.

  2. Electronic configuration of S(Z = 16) 2, 8, 6.

  3. $2\text{FeSO}_4.7\text{H}_2\text{O(s)}\xrightarrow{\ \ \ \text{heat}\ \ \ }\text{Fe}_2\text{O}_3(\text{s})+\text{SO}_2(\text{g})+\text{SO}_3(\text{g})+7\text{H}_2\text{O(g)}$

  4. Fe2O3 (basic oxide), SO2(acidic oxide), SO3(acidic oxide).

  5. Sulphur is a member of group 16 and period 3.

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

Similar questions

When a mixture of gases X and Y is compressed to 300atm pressure and then passed over a catalyst consisting of a mixture of zinc oxide and chromium oxide (heated to a temperature of 300°C), then an organic compounds Z having the molecular formula CH4O is formed. X is a highly poisonous gas which is formed in appreciable amounts when a fuel burns in a limited supply of air; Y is a gas which can be made by the action of a dilute acid on an active metal; and Z is a liquid organic compound which can react with sodium metal to produce hydrogen gas:
  1. What are X, Y and Z?
  2. Write a balanced chemical equation of the reaction which takes place when X and Y combine to form Z. Indicate the conditions under which the reaction occurs.
On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed.
  1. Write a balanced chemical equation of the reaction.
  2. Identity the brown gas X evolved.
  3. Identity the type of reaction.
  4. What could be the pH range of aqueous solution of the gas X?
A black metal oxide XO is used as a catalyst in the preparation of oxygen gas from potassium chlorate. The oxide XO is also used in ordinary dry cells. The metal oxide XO cannot be reduced satisfactorily with carbon to form metal X.
  1. Name the metal X.
  2. Name the metal oxide XO.
  3. Which reducing agent can be used to reduce XO to obtain metal X?
  4. Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.
Mendeleev predicted the existence of certain elements not known at that time and named two of them as Eka-silicon and Eka-aluminium.
  1. Name the elements which have taken the place of these elements.
  2. Mention the group and the period of these elements in the Modern Periodic Table.
  3. Classify these elements as metals, non-metals or metalloids.
  4. How many valence electrons are present in each one of them?
A compound C (molecular formula, C2H4O2) reacts with Na-metal to form a compound R and evolves a gas which burns with a pop sound. Compound C on treatment with an alcohol A in presence of an acid forms a sweet smelling compound S (molecular formula, C3H6O2). On addition of NaOH to C, it also gives R and water. S on treatment with NaOH solution gives back R and A.

Identify C, R, A, S and write down the reactions involved.

When water is added gradually to a white solid X, a hissing sound is heard and a lot of heat is produced forming a product Y. A suspension of Y in water is applied to the walls of a house during white washing. A clear solution of Y is also used for testing carbon dioxide gas in the laboratory.
  1. What could be solid X? Write its chemical formula.
  2. What could be product Y? Write its chemical formula.
  3. What is the common name of the solution of Y which is used for testing carbon dioxide gas?
  4. Write chemical equation of the reaction which takes place on adding water to slid X.
  5. Which characteristic of chemical reactions is illustrated by this example?
A solid substance P which is very hard is used in the construction of many buildings, especially flooring. When substance P is heated strongly, it decomposes to form another solid Q and a gas R is given out. Solid Q reacts with water with the release of a lot of heat to form a substance S. When gas R is passed into a clear solution of substance S, then a white precipitate of substance T is formed. The substance T has the same chemical composition as starting substance P.
  1. What is substance P? Write its common name as well as chemical formula.
  2. What is substance Q?
  3. What is gas R?
  4. What is substance S? What is its clear solution known as?
  5. What is substance T? Name any two natural forms in which substance T occurs in nature.
Write the names and symbols of two very reactive metals belonging to group 1 of the periodic table. Explain by drawing electronic structure, how either one of the two metals reacts with a halogen. With which name is the bond formed between these elements known and what is the class of the compound so formed known? State any four physical properties of such compounds.
Write the chemical formula of ammonium chloride. Explain why an aqueous solution of ammonium chloride is acidic in nature? Illustrate your answer with the help of a chemical equation.
Arrange the following elements in the increasing order of their metallic character Mg, Ca, K, Ge, Ga.