|
No chemical reaction takes place when granules of a solid A, are mixed with the powder of another solid B
|
|
1
|
809
|
March 29, 2019
|
|
(a) What is meant by corrosion? Name any two methods used for the prevention of corrosion
|
|
1
|
3790
|
March 29, 2019
|
|
(a) What is a reactivity series? Describe an activity to develop a reactivity series
|
|
1
|
1597
|
March 29, 2019
|
|
(a) What are ionic compounds? List any four physical properties of these compounds
|
|
1
|
1787
|
March 29, 2019
|
|
Give reasons for the following: (i) Metals are regarded as electro-positive elements
|
|
1
|
1941
|
March 29, 2019
|
|
How is an alloy made? List two proposes of making alloys and mention the constituents and two properties of each of the following alloys:
|
|
1
|
900
|
March 29, 2019
|
|
Give reasons for the following observations: (i) Ionic compounds in general have high melting and boiling points
|
|
1
|
2850
|
March 29, 2019
|
|
1. What is an alloy? How does it differ from an amalgam?
|
|
1
|
1107
|
March 29, 2019
|
|
What is meant by ‘rusting’? With labelled diagrams describe an activity to find out the conditions under which iron rusts
|
|
1
|
10843
|
March 29, 2019
|
|
(i) Arrange the following metals in decreasing order of their reactivity: Fe, Zn, Na, Cu, Ag
|
|
1
|
1735
|
March 29, 2019
|
|
(a) Name a metal for each case: (i) It does not react with cold as well as hot water but reacts with steam
|
|
1
|
6256
|
March 29, 2019
|
|
Give reasons for the following: (a) Metals can be given different shapes according to our needs
|
|
1
|
5179
|
March 29, 2019
|
|
Give reasons for the following: (a) Gold and silver are used to make jewellery
|
|
1
|
2902
|
March 29, 2019
|
|
What are amphoteric oxides? Choose the amphoteric oxides from amongst the following oxides:
|
|
1
|
11912
|
March 29, 2019
|
|
Explain the following terms by giving one exafhple of each:
|
|
1
|
441
|
March 29, 2019
|
|
Give reasons for the following: (i) Metals are regarded as electro-positive elements
|
|
1
|
684
|
March 29, 2019
|
|
Explain the Froth Flotation?
|
|
1
|
475
|
March 29, 2019
|
|
(a) What would you observe when you put: (i) Some zinc pieces into blue copper sulphate solution?
|
|
1
|
10163
|
March 29, 2019
|
|
Give reasons for the following: (a) Na, K and Ca metals form hydride by combination with hydrogen gas, but most other metals do not
|
|
1
|
3165
|
March 29, 2019
|
|
Give reasons for the following: (a) Zinc oxide is considered as an amphoteric oxide
|
|
1
|
12373
|
March 29, 2019
|
|
Write chemical equations for reactions taking place when:
|
|
1
|
1056
|
March 29, 2019
|
|
Give reason for the following: (a) Silicon counts among metalloids
|
|
1
|
2211
|
March 29, 2019
|
|
(i) How are metalloids different from metals? Name a metalloid
|
|
1
|
1261
|
March 29, 2019
|
|
Write chemical equations for the reactions taking place when: (i) Zinc sulphide is heated in air
|
|
1
|
1083
|
March 29, 2019
|
|
Give reasons for the following: (i) Metals conduct electricity
|
|
1
|
1690
|
March 29, 2019
|
|
(a) What are strategic metals? Give one example also. (b) State the reason for the following behaviour of zinc metal:
|
|
1
|
1506
|
March 29, 2019
|
|
Curd is not kept in copper and brass utensils. Why?
|
|
1
|
2313
|
March 29, 2019
|
|
(a) Distinguish between ionic and covalent compounds in the following properties:
|
|
1
|
576
|
March 29, 2019
|
|
Name the metals which reacts violently with cold water. Write any three observations
|
|
1
|
547
|
March 29, 2019
|
|
Choose the metal (from the list given below) which can displace zinc from zinc sulphate solution
|
|
1
|
1643
|
March 29, 2019
|
