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Question & Answer Forum

Next time you have a doubt while studying, you know where to go. By simply posting your questions on Question & Answer Forum, you can have them answered by academic experts. You can also find related videos and explanations for better understanding.

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Swathi answered 4 year(s) , 1 month(s) ago

Aluminium is a highly reactive metal. But why it is used for making utensils for cooking?

Aluminium is highly reactive metal. When aluminium is exposed to air it reacts with oxygen and forms a white thin layer of aluminium oxide on its surface. This layer forms protective coating on aluminium and

...

Asked by Swathi

Dec 31

  • 4 Answers
  • 2 Likes
  • 34730 Views
Satyanarayana answered 4 year(s) , 6 month(s) ago

(6) Show the formation of Na2O and MgO by the transfer of electrons

Ans: Atomic number of Sodium (Na) – 11
Electronic configuration of Sodium – 1s 2 2s 2 2p 6 3s 1
It has one valence electron, it will lose one elec...

Asked by R murali

Jul 18

  • 1 Answer
  • 1 Like
  • 32915 Views
Prathik answered 4 year(s) , 4 month(s) ago

Thermit reaction

Ans: The process of igniting Aluminium and Ferric oxide is called thermite reaction.  This is an exothermic reaction. Iron obtained in this process is in molten state.
Fe...

Asked by Rujuta

Sep 24

  • 2 Answers
  • 3 Likes
  • 22787 Views
Swathi answered 3 year(s) ago

When a green iron salt is heated strongly its colour changes to black and odor of burning sulphur is given out

    1) Ferrous Sulphate

2) Thermal decomposition

3) 2 FeSO4 (s)   Heat →   Fe2O3 (s)+ SO2 (g) + SO3 (g)
        Ferrous

...

Asked by Keisam

Jan 19

  • 1 Answer
  • 4 Likes
  • 20473 Views
Swathi answered 3 year(s) , 9 month(s) ago

When you add sodium hydrogen carbonate to acetic acid in a test tube, a gas liberates immediately with brisk effervescence. Name this gas. Describe the method of testing this gas

Sodium hydrogencarbonate on reaction with acetic acid releases carbon dioxide gas.
NaHCO 3 + CH 3COOH → CH 3COONa + H 2O + CO 2

...

Asked by Adithyan

Apr 25

  • 1 Answer
  • 0 Like
  • 16904 Views
Syeda answered 1 year(s) , 8 month(s) ago

(3) Why is sodium chloride soluble in water but not in kerosene or petrol?

Answer.

Sodium chloride is an ionic molecule. There exists electronegativity difference between Sodium and Chlorine, which gives polarity to the molecule. Thus sodium chloride is polar mo

...

Asked by R murali

Jul 18

  • 2 Answers
  • 0 Like
  • 14837 Views
Swathi answered 4 year(s) , 4 month(s) ago

A few drops of sulphuric acid are added into water before electrolysis

Ans :Electrolysis of pure water is very low because water is an covalent compound so it can't ionize to release ions. To increase the conductivity of water a few drops of sulphuric acid is added .Being a strong...

  • 1 Answer
  • 4 Likes
  • 13486 Views
Swathi answered 4 year(s) , 1 month(s) ago

Why copper is added to pure gold for making ornaments?

Pure gold is very soft and it is not used for making jewellery. Copper or silver is added to pure gold to make it hard. Pure gold is called 24 carat gold. This is alloyed with silver or copper to make it har

...

Asked by Swathi

Jan 2

  • 2 Answers
  • 0 Like
  • 11370 Views
Swathi answered 4 year(s) , 6 month(s) ago

An element reacts with oxygen to give a compound with high melting point. This compound is also soluble in water. The element is likely to be

When carbon reacts with oxygen it forms carbon dioxide. this carbon dioxide is a gas. gases do not possess melting point. so option B is not correct
Silicon reacts with oxygen and forms silicon dioxide....

Asked by R murali

Jul 18

  • 1 Answer
  • 3 Likes
  • 10623 Views
Satyanarayana answered 4 year(s) , 10 month(s) ago

Calcination and roasting

Ans: Calcination:
Conversion of metals into their oxides at high temperature in absence of air (or) limited supply of air is called calcination.
Carbona...

Asked by San

Apr 10

  • 1 Answer
  • 2 Likes
  • 8223 Views
Uday answered 5 year(s) , 6 month(s) ago

why are electric wires coated with substances like pvc?

ELECTRIC WIRES ARE COATED WITH SUBSTANCE LIKE PVC  TO PREVENT FROM ELECTRIC SHOCK AND ALSO PVC IS INSULATOR(BAD CONDUCTOR OF ELECTRICITY).

  • 1 Answer
  • 2 Likes
  • 8063 Views
Satyanarayana answered 5 year(s) , 6 month(s) ago

Molecular formula of Sulphur is S8, but why in chemical reaction sulphur is written as S and not S8

Ans: 'S' is the symbol for the elemental sulphur and 'S 8 'is the symbol for molecular form.
 It can be written as S₈ but the balancing of chemical equation need be changed...

Asked by T k

Jul 19

  • 1 Answer
  • 2 Likes
  • 7829 Views
Satyanarayana answered 4 year(s) , 6 month(s) ago

(2) Name the cation and anion present in Mgcl2, ZnSo4

Ans: In general in ionic compound metals are cations and non-metals are anions. As metals are electropositive in nature.
In the given molecules
(i)                 MgCl2 – Mg is Cation (Mg...

Asked by R murali

Jul 18

  • 1 Answer
  • 0 Like
  • 7745 Views
Swathi answered 4 year(s) , 6 month(s) ago

(5) Why do ionic compounds do not conduct electricity in solid state. But conduct electricity in molten state?

Ionic compounds are composed of two elements. The ionic bond between these two elements is strong. In solid state there is no availability of free electrons and also there is no probability for the formation of...

Asked by R murali

Jul 18

  • 1 Answer
  • 0 Like
  • 7494 Views
Satyanarayana answered 5 year(s) , 6 month(s) ago

A reddish brown metal X on heating forms a black coating of oxide Y on its surface.The metal does not react with dil.HCl and dil.H2SO4.It reacts with hot conc.H2SO4 to givea pungent smelling gas simil

Ans: The metal in reddish brown colour is Copper (Cu).
        On heating it forms black colored oxide
       2Cu + O₂ → CuO
Cu on reaction with conc.H₂SO₄ produces SO₂...

Asked by Inu

Jul 27

  • 1 Answer
  • 0 Like
  • 5616 Views
Syeda answered 1 year(s) , 8 month(s) ago

(8)(A) What type of chlorides are formed by metals and what type of chlorides are formed by non-metals? (B) Why do metals form ionic chlorides are formed whereas non-metals form covalent chlorides?

Answer.

Generally metals forms ionic chloride and non metals forms covalent chlorides.

The electro negativity difference between and metal and chloride is more hence they form ionic compoun

...

Asked by R murali

Jul 12

  • 2 Answers
  • 1 Like
  • 5300 Views
Swathi answered 4 year(s) , 6 month(s) ago

(7)(A) how can you test that non-metallic oxides are acidic in nature? Explain with an example (B) how can you test that non-metallic oxides are basic in nature? Explain with an example

Take a magnesium ribbon. burn this magnesium ribbon in air. collect the ash dissolve the ash in water then dip a red litmus paper in the solution. The  red litmus turns into blue color. this indicates the solut...

Asked by R murali

Jul 12

  • 1 Answer
  • 0 Like
  • 5195 Views
Swathi answered 3 year(s) , 9 month(s) ago

How find the position of an element with atomic number 16 in the periodic table.

Atomic number of an element is 16.
To know its position in periodic table first we should write the electronic configuration of the element.
Electronic configuration of the element - 2 8 6.
...

Asked by Adithyan

Apr 25

  • 1 Answer
  • 0 Like
  • 5142 Views
Inu commented 5 year(s) , 6 month(s) ago

name two metals which react with very dilute HNO3 (5%) to liberate H2 (g). Give chemical equations.

Ans:  The metals like Magnesium and Calcium reacts with dil.HNO₃ producing H₂ gas.
            Mg + 2HNO₃ → Mg(NO₃)₂ + H₂
            Ca + 2HNO₃ → Ca(NO₃)₂ + H₂
 ...

Asked by Inu

Jul 24

  • 1 Answer
  • 1 Like
  • 4515 Views
Abishek answered 3 year(s) , 8 month(s) ago

Metal highly malleable and ductile

I WOULD SAY GOLD AS A 2 GRAM OF GOLD  CAN BE DRAWN TO KILOMETRES.

HOPE THIS ANSWER HELPED YOU

Asked by Inu

Jul 25

  • 5 Answers
  • 0 Like
  • 3811 Views
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