1. Why can jewellery be made out of gold and silver easily?
2. Why do diamond and graphite have different physical properties?
3. Name any one metal that does not react with dilute H2SO4 to liberate H2.
4. Write the name given to the alloy of lead and tin that which is used for welding electrical wires together.
5. Name one non–metal with metallic luster.
6. Name the various types of ores from which metals are extracted. Which type of ore is the most common for most metals and why?
7. Why are metals used for making cooking vessels? Why copper and silver are most commonly used for making cooking vessels?
8. Define minerals, ore and gangue
9. Why do metals and non–metals react? Explain with the help of an example
10. What is the need of refining? What is electrolytic refining?
1. Because gold and silver are malleable and ductile.
2. Because the arrangement of atoms in the two is different.
3. Copper or silver
6. The ores used in the extraction of metals are
(i) oxide ore (ii) sulphate ore
(iii) carbonate ore (iv) halide ore
The ores of many metals exist as oxides. This is because oxygen is very reactive element and is present in a large amount on the earth.
07 Metals are generally good conductors of heat and have high melting points. So metals can withstand high temperature without melting. Metals are malleable thus, they can be given various shapes Silver and copper are best conductors of heat and they are malleable. Hence, they are preferred for making cooking vessels
08. Minerals: The elements or compounds, which occur naturally in the earth’s crust, are known as minerals. E.g. Magnesium oxide, ferrous oxide.
Ores: At some places, minerals contain a very high percentage of a particular metal and the metal can be profitably extracted from it. These minerals are called ores. E.g. Ore of iron in hematite.
Gangue: Ores mined from the earth are usually contaminated with large amounts of impurities such as soil, sand etc and are called gangue. E.g. gangue present along with hematite is silicon dioxide.
09. Metals are electropositive elements and have a tendency to lose electrons and acquire a positive charge while non–metals are electronegative elements and tend to gain electrons and acquire a negative charge. By doing this both metals and non metals attain the stable noble gas configuration. For the metals and non–metals to react, the electron lost by the metal atom will have to be gained by the non metal atom. The ions formed in this way are held together by strong electrostatic forces of attraction which results in the formation of ionic compounds.
10.The metals produced by various reduction processes are not pure. They contain impurities, which must be removed to obtain pure metals. The process of purification of metals is known as REFINING.
Most widely used method for refining impure metals is electrolytic
refining. Electrolytic refining means purification of metals by electrolysis. Many metals, such as copper, zinc, tin nickel, silver, gold etc are refined electrolytically.
Click here for further study CBSE Extra Score Notes X Metals and Non Metals