8. Metallurgy | Part 2 | Science I | Class 10

The blog presents the short Questions and Answers of the Chapter 1, Metallurgy, from Science Part I of Class 10 from Maharashtra State Board. These can be very useful for students preparing for SSC Board exams as well as competitive exams, as it includes the objective type basic concepts & fundamentals.

Q16. Write the reactions of non-metals with oxygen ?

Ans. The reaction of nonmetals with oxygen proceeds as follows:
(a) Generally, nonmetals combine with oxygen to form acidic oxides.

Reaction of non-metals with oxygen

(b) In some cases, neutral oxides are formed.
Partial Combustion

Neutral oxide is formed

Q17. Write the reaction of non-metals with water ?

Ans. Generally, nonmetals do not react with water, except the halogens.
For example, chlorine on dissolving in water gives the following reaction.

Reaction of non-metals with water

Q18. Write the reaction of non-metals with dilute acids ?

Ans. Generally, nonmetals do not react with dilute acids, halogens are exception to this. For example, chlorine reacts with dilute hydrobromic acid by the following reaction.

Reaction of non-metals with dilute acids

Q19. Write the reaction of non-metals with hydrogen ?

Ans. Nonmetals react with hydrogen under certain condition (such as proper temperature, pressure, use of catalyst, etc.)

S + H2 −−→ H2 S
N2 + 3 H2 −−→ 2 NH3

Q20. What are ionic compounds ?

Ans. The compounds formed from two units, namely cation and anion are called ionic compounds.

Q21. What are ionic bonds ?

Ans. As the cation and anion are oppositely charged, there is an electrostatic force of attraction between them. This force of attraction between cation and anion is also called as the ionic bond.

Q22. Why the ionic compound is electrically neutral ?

Ans. The number of cations and anions in a compound and the magnitude of the electric charge on them is such that the positive and negative charges balance each other. As a result, an ionic compound is electrically neutral.

Q23. What are the two important factors responsible for a certain crystal structure ?

Ans. The two of the important factors responsible for a certain crystal structure are :
(a) Size of the positively and negatively charged ions.
(b) Magnitude of the electrical charge on the ions.

Q24. Why is the melting points of ionic compounds high ?

Ans. The electrostatic attraction in the neighbouring ions with opposite charges is very strong. Hence, the melting points of ionic compounds are high.

Q25. Write the general properties of ionic compounds.

Ans. The general properties of ionic compounds are :
(a) The attractive force between the positively and negatively charged
ions is strong Therefore, the ionic compounds exist in solid state and are hard.
(b) The ionic compounds are brittle and can be broken into pieces by applying pressure.
(c) The intermolecular force of attraction is high in ionic compounds, therefore, the
melting and boiling points of ionic compounds are high.
(d) Ionic compounds are water soluble.
(e) The ionic compounds cannot conduct electricity when in solid state, however, in the fused/molten state they can conduct electricity.

Q26. Ionic compounds are soluble in water whereas insoluble in solvents like kerosene, Why ?

Ans. Ionic compounds are soluble in water whereas insoluble in solvents like kerosene because:
(i) The water molecules orient in a particular manner around the ions separated by dissociation process.
(ii) As a result of this a new force of attraction is established between the ion and the surrounding water molecules,
replacing the original intermolecular attraction; and aqueous solutions of ionic compounds are formed.
(iii) Ionic compounds are however, insoluble in solvents like kerosene, because unlike water a new attractive force can not be established in these solvents.

Q27. The ionic compounds cannot conduct electricity in solid state, but conduct electricity in molten or fused state, why ?

Ans. The ionic compounds cannot conduct electricity in solid state, but conduct electricity in molten or fused state, because :
(i) In solid state the ions cannot leave their places.
(ii) In the fused/molten state they can conduct electricity, as in this state the ions are mobile.
(iii) The aqueous solutions of ionic compounds contain the dissociated ions. On passing current through the solution the ions move to the oppositely charged electrodes and conduct electricity.

Q28. Why ionic compounds are called electrolytes ?

Ans. Because to the electrical conductivity of ionic compounds in fused and dissolved state the compounds are called electrolytes.

Q29. What is metallurgy ?

Ans. The science and technology regarding the extraction of metals from ores and their purification for the use is called metallurgy.

Q30. What do you mean by minerals ?

Ans. The compounds of metals that occur in nature along with the impurities are called minerals.

************************

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.