When hydrogen is passed over a black solid compound A, the products are 'a colourless liquid' and 'a reddish brown metal B.' Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO, to the other.
Write an equation for the reaction between hydrogen and substance A.

When hydrogen is passed over a black solid compound A, the products are 'a colourless liquid' and 'a reddish brown metal B.' Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO3, to the other. Name the substances A and B.

When hydrogen is passed over a black solid compound A, the products are 'a colourless liquid' and 'a reddish brown metal B.' Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO, to the other. Is there any reaction between substance B and dilute hydrochloric acid ? Give reasons for your answer.

When hydrogen is passed over a black solid compound A, the products are 'a colourless liquid' and 'a reddish brown metal B.' Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO, to the other. What happens to substance A when it reacts with hydrogen ? Give reasons for your answer.

When hydrogen is passed over a black solid compound A, the products are .a colourless liquid. and .a reddish brown metal B.. Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO_3 to the other. Is there any reaction between substance B and dilute hydrochloric acid ? Give reasons for your answer.

When hydrogen is passed over a black solid compound A, the products are .a colourless liquid. and .a reddish brown metal B.. Substance B is divided into two parts, each placed in separate test tubes. Dilute HCl is added to one part of substance B and dilute HNO_3 to the other. Give two tests for the colourless liquid formed in the experiment. What does it signifies ?

An inorganic compound (X) gives a brick red flame on performing flame test. This compound gives the following tests also. (a) Smells of chlorine when placed in moist air. (b) If KI and CH_(3)COOH are added to the suspension in water, a brown colour is obtained. Identify (X) and write down equations for reactions at steps (a) and (b) .

When potassium iodide solution is added to a solution of lead (II) nitrate in a test tube, a precipitate is formed. (a) What is the colour of this precipitate? Name the compound precipitated. (b) Write the balanced chemical equation for this rection. (c) List two types of reactions in which this reaction can be placed.

(a) Why does calcium start floating when added to water? (b) Most of the metals do not give hydrogen while reacting with nitric acid. Why? (c ) Write equation for the reaction of iron with steam. Name the compound of iron obtained.

Read the following paragraph and answer the questions given below , Stable equilibrium is of various types . Mechanical equilibrium is achieved when all particles are at rest and total potential energy of the system is minimum . At any stage where particles are at rest but the system is not at stable equilibrium as it can reduce its potential energy by reverting to another position, is called metastable equilibrium . Thermal equilibrium is result from the absence of temperature gradients in the system. Chemical equilibrium is obtained when no further reaction occurs between reacting substances, i.e forward and reverse rates of reaction are equal. When steam with solid iron at high temperature Fe_3O_4(s) and hydrogen gas are produced . But the reaction never goes to completion. This is because as the products are formed the reaction proceeds in reverse direction and when rate of reverse reaction is equal to rate of forward reaction , the concentration of reactants and products become constant and equilibrium is reached. When two reactants (A) and (B) are mixed to give products (C) and (D) the concentration quotient (Q) at initial stage of the reaction

A reddish brown coloured metal is used in electrical wires. When powdered and heated strongly in an open china dish, its colour turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on the above information, answer the following question. (i) Name the metal and the black coloured substance formed. (ii) Write balanced chemical equations for both the reactions.