(a)What is meant by saying that the metals are malleable and ductile? Explain with examples.
(b)Name two metals which are both malleable and ductile.
(c)Which property of iron metal is utilized in producing iron sheets required for making buckets?
(d)Which property of copper metal is utilized in making thin wires?
Name two metals which react violently with cold water. Write any three observations you would make when such a metal is dropped into water. How would you identify the gas evolved, if any, during the reaction?
In the given reaction sodium oxide reacts with water. What product will form in the given reaction?
Na2O + H2O → ?
**Fill in the following blanks with suitable words:**
(a) Magnesium liberates _______________ gas on reacting with hot boiling water.
(b) The white powder formed when magnesium ribbon burns in oxygen is of ___________.
(c) Ordinary aluminium stripes are not attacked by water because of the presence of a layer of _____________ on the surface of aluminium.
(d) A metal having low melting point is _________ but a non-metal having very high melting point is _____________.
(e) Calcium is a __________________ reactive metal than sodium.
Give reasons for the following:
Blue colour of copper sulphate solution is destroyed when iron fillings are added to it.
Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.
Name the non-metal which is used:
(a) To convert vegetable oil into vegetable ghee (solid fat).
(b) As a rocket fuel (in liquid form).
(c) To make electrodes of dry cells.
(d) To preserve food materials.
(e) In the vulcanization of rubber.
Name two metals which are used:
(a)For making electric wires.
(b)For making domestic utensils and factory equipment.
(c)For making jewellery and to decorate sweets.
What is meant by “brittleness”? Which type of elements usually shows brittleness: metals or non-metals?
Name the metal which has been placed:
(a)At the bottom of the reactivity series
(b)At the top of the reactivity series
(c)Just below copper in the reactivity series
(a)Name one metal which is stored in kerosene oil.
(b)Name one non-metal which is stored under water.
Which property of copper and aluminium makes them suitable:
(a)For making cooking utensils and boilers?
(b)For making electric wires?
What is aqua-regia? Name two special metals which are insoluble in common reagents but dissolve in aqua-regia.
What changes in the colour of iron nails and copper sulphate solution do you observe after keeping the iron nails dipped in copper sulphate solution for about 30 minutes?
From amongst the metals sodium, calcium, aluminium, copper and magnesium, name the metal:
(i)Which reacts with water only on boiling, and
(ii)Another which does not react even with steam.
State whether the following statement is true or false:
Non-metals react with dilute acids to produce a gas which burns with a pop sound.
Why are metals called electropositive elements whereas non-metals are called electronegative elements?
(a)Name the most abundant metal in the earth’s crust.
(b)Name the most abundant non-metal in the earth’s crust.
(a)What happens when calcium reacts with water? Write the chemical equations of the reaction of calcium with water.
(b)Write the chemical equation of the reaction which takes place when iron reacts with dilute sulphuric acid. What happens when the gas produced is ignited with a burning matchstick?
(a)Write one reaction in which aluminium oxide behaves as a basic oxide and another in which it behaves as an acidic oxide.
(b)What special name is given to substances like aluminium oxide.
(c)Name another metal oxide which behaves like aluminium oxide.
You are given samples of three metals- sodium, magnesium and copper. Suggest any two activities to arrange them in order of their decreasing reactivities.
What is the action of water on (a) sodium (b) magnesium and (c) aluminium? Write equations of the chemical reactions involved.
(a)Give one example, with equation, of the displacement of hydrogen by a metal from an acid.
(b)Name two metals (other than zinc and iron) which can displace hydrogen from dilute hydrochloric acid?
(a)Why is sodium kept immersed in kerosene oil?
(b)Why is white phosphorus kept immersed under water?
(c)Can we keep sodium immersed under water? Why?
(a)Why does aluminium not react with water under ordinary conditions?
(b)Name two metals which can displace hydrogen from dilute acids.
(c)Name two metals which cannot displace hydrogen from dilute acids.
(a)State one use of each of the following non-metals:
Hydrogen, carbon (as Graphite), Nitrogen, Sulphur
(b)Name the metal which is used in making thermometers.
(a)Describe the reaction of potassium with water. Write the equation of the reaction involved.
(b)Write an equation of the reaction of iron with steam. Indicate the physical states of all the reactants and products.
(c)Which gas is produced when dilute hydrochloric acid is added to a reactive metal?
A copper plate was dipped in AgNO3 solution. After certain time, silver from the solution was deposited on the copper plate. State the reason why it happened. Give the chemical equation of the reaction involved.
(a) Arrange the following metals in order of their chemical reactivity, placing the most reactive metal first:
Magnesium, Copper, Iron, Sodium, Zinc, Lead, Calcium.
(b) What happens when a rod of zinc metal is dipped into a solution of copper sulphate? Give chemical equation of the reaction involved.
(a)What happens when calcium reacts with chlorine? Write an equation for the reaction which takes place.
(b)What happens when magnesium reacts with very dilute nitric acid? Write an equation for the reaction
(a)How do metals react with hydrogen? Explain with an example.
(b)How do non-metals react with hydrogen? Explain with an example
(a)Explain why, metals usually do not liberate hydrogen gas with dilute nitric acid.
(b)Name two metals which can, however, liberate hydrogen gas from very dilute nitric acid.
(a)What type of oxides are formed when non-metals react with oxygen? Explain with an example.
(b)What type of oxides are formed when metals combine with oxygen? Explain with the help of an example.
(a)What is the nature of the oxide SO2? What happens when it is dissolved in water? Write the chemical equation of the reaction involved.
(b)What is the nature of the oxide Na2O? What happens when it is dissolved in water? Write the chemical equation of the reaction involved.
(a)What are amphoteric oxides? Give two examples of amphoteric oxides.
(b)Choose the acidic oxides, basic oxides and neutral oxides from the following:
Na2O; CO2.; CO; SO2; MgO; N2O; H2O
(c)Which of the following are amphoteric oxides:
Mgo, ZnO, P2O3, Al2O3, NO2
(a) State any three differences between the physical properties of metals and non-metals.
(b) Differentiate between metals and non-metals on the basis of their chemical properties.
(c) State three reasons (of which at least one must be chemical) for believing that sodium is a metal.
(d) State three reasons (of which at least one must be chemical) for believing that sulphur is a non-metal.
(e) Which non-metal has been placed in the reactivity series of metals?
Which of the following pair of reactants can undergo a displacement reaction under appropriate conditions?
(a) MgSO4 + Fe
(b) ZnSO4 + Fe
(c) MgSO4 + Pb
(d) CuSO4 + Fe
Which one of the following four metals would be displaced from the solution of its salt by other three metals:
An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be:
An element E reacts with water to form a solution which turns phenolphthalein solution pink. The element E is most likely to be:
A metal less reactive and another metal more reactive than hydrogen are:
(a) Aluminium and lead
(b) Iron and magnesium
(c) Copper and tin
(d) Copper and mercury
Zinc Oxide is a metal oxide. Which of the following term best describes the nature of zinc oxides:
(a) An acidic oxide
(b) A basic oxide
(c) An amphoteric oxide
(d) A neutral oxide
The elements whose oxide can turn litmus solution red are:
(a) Lithium and sodium
(b) Copper and potassium
(c) Carbon and hydrogen
(d) Phosphorus and sulphur
The elements whose oxides can turn litmus solution blue are:
(a) Carbon and sulphur
(b) Sodium and carbon
(c) Potassium and magnesium
(d) Magnesium and sulphur
An element X forms two oxides XO and XO2. The oxide XO is neutral but XO2 is acidic in nature. The element X is most likely to be:
The metals which can produce amphoteric oxides are:
(a) Sodium and aluminium
(b) Zinc and potassium
(c) Calcium and sodium
(d) Aluminium and zinc
An element X reacts with hydrogen, when heated to form a covalent hydride H2X. If H2X has a smell of rotten eggs, the element X is likely to be:
The elements whose oxides can turn phenolphthalein solution pink are:
(a) Na and K
(b) K and C
(c) Na and S
(d) K and P
Out of aluminium, Copper, calcium, and tin, the most reactive metal is:
You are given a solution of AgNO3. Which of the following do you think cannot displace Ag from AgNO3 solution ?
An element is soft and can be cut with a knife. It is very reactive and cannot be kept open in the air. It reacts vigorously with water. The element is most likely to be:
”Is malleable and ductile”. This best describes:
(a) A metal
(b) A compound
(c) A non-metal
(d) A solution
Metals are said to be shiny. Why do metals generally appear to be dull? How can their brightness be restored?
(a) What is meant by the reactivity series of metals? Arrange the following metals in an increasing order of their reactivities towards water:
Zinc, Iron, Magnesium, Sodium
(b) Hydrogen is not a metal but still it has been assigned a place in the reactivity series of metals. Why ?
(c) Name one metal more reactive and another less reactive than hydrogen.
(d) Name one metal which displaces copper from copper sulphate solution and one which does not.
(e) Name one metal which displaces silver from silver nitrate solution and one which does not.
(a) Define non-metals. Give five examples of non-metals.
(b) Name a non-metal which conducts electricity.
(c) Name a non-metal having lustre (shining surface).
(d) Name a non-metal which is extremely hard.
(e) How do non-metals react with oxygen? Explain with an example. Give equation of the reaction involved. What is the nature of the product formed ? How will you demonstrate it?
(a) What are metals? Name five metals.
(b) Name a metal which is so soft that it can be cut with a knife.
(c) Name the metal which is the best conductor of heat and electricity.
(d) What happens when a metal reacts with dilute hydrochloric acid? Explain with the help of an example.
(e) Write the equations for the reactions of:
(i) Magnesium with dilute hydrochloric acid
(ii) Aluminium with dilute hydrochloric acid
(iii) Zinc with dilute hydrochloric acid
(iv) Iron with dilute hydrochloric acid
Name the products formed in each case. Also indicate the physical states of all the substances involved.
(a)Name two physical properties each of sodium and carbon in which their behaviour is not as expected from their classification as metal and non-metal respectively.
(b)Name two metals whose melting points are so low that they melt when held in the hand.
You are given a dry cell, a torch bulb with holder, wires and crocodile clips. How would you use them to distinguish between samples of metals and non-metals?
A copper coin is kept immersed in a solution of silver nitrate for some time. What will happen to the coin and the colour of the solution?
(a)With the help of examples, describe how metal oxides differ from non-metal oxides.
(b)Which of the following elements would yield: (i) an acidic oxide, (ii) a basic oxide, and (iii) a neutral oxide?
Na, S, C, K, H
A zinc ore gave CO2 on treatment with a dilute acid. Identify the ore and write its chemical formula
(a)Write down the electronic configuration of (i) magnesium atom, and (ii) magnesium ion. (At. No. of Mg = 12)
(b)Write down the electronic configuration of (i) sulphur atom, and (ii) sulphide ion, (At. No. of S = 16)
What type of chemical bonds are present in a solid compound which has a high melting point, does not conduct electricity in the solid state but becomes a good conductor in the molten state?
State whether the following statement is true or false:
The aqueous solution of an ionic compound conducts electricity because there are plenty of free electrons in the solution.
The atomic number of an element X is 8 and that of element Y is 12. Write down the symbols of the ions you would expect to be formed from their atoms.
(a) The atomic number of sodium is 11. What is the number of electrons in Na+?
(b) The atomic number of chlorine is 17. What is the number of electrons in Cl-?
(a) What do we call those particles which have more or less electrons than the normal atoms?
(b) What do we call those particles which have more electrons than the normal atoms?
(c) What do we call those particles which have less electrons than the normal atoms?
What is the name of the chemical bond formed:
(a) By the sharing of electrons between two atoms?
(b) By the transfer of electrons from one atom to another?
Give reason for the following :
Carbonate and sulphide ores are usually converted into oxides during the process of extraction of metals.
(a) Giving one example each, state what are (i) ionic compounds, and (ii) covalent compounds.
(b) Compare the properties of ionic compounds and covalent compounds.
Draw the electron-dot structures of the following compounds and state the type of bonding in each case:
What is the difference between a cation and an anion? How are they formed? Give the names and symbols of one cation and one anion.
Describe how sodium and chlorine atoms are changed into ions when they react with each other to form sodium chloride, NaCl. What is the name given to this type of bonding?
What type of bonding would you expect between the following pairs of elements?
(i) Calcium and Oxygen
(ii) Carbon and Chlorine
(iii) Hydrogen and Chlorine.
Draw the electron-dot structure of a hydrogen chloride molecule:
(i) Which inert gas does the H atom in HCl resemble in electron arrangement?
(ii) Which inert gas does the Cl atom in HCl resemble in electron arrangement?
(i)Write electron-dot structures for magnesium and oxygen.
(ii)Show the formation of MgO by the transfer of electrons.
(iii)What are the ions present in this compound?
(a)What are noble gases? What is the characteristic of the electronic configuration of noble gases?
(b)What is the cause of chemical bonding (or chemical combination) of atoms of elements?
Give the formulae of the compounds that would be formed by the combination of the following pairs of elements:
(a) Mg and N2
(b) Li and O2
(c) Al and Cl2
(d) K and H
Using electron-dot diagrams which show only the outermost shell electrons, show how a molecule of nitrogen, N2, is formed from two nitrogen atoms. What name is given to this type of bonding?
(a) Name one ionic compound containing chlorine and one covalent compound containing chlorine.
(b) How will you find out which of the water soluble compound A or B is ionic?
(a) Explain why, ionic compounds conduct electricity in solution whereas covalent compounds do not conduct electricity.
(b) Which of the following will conduct electricity and which not?
MgCl2, CCl4, NaCl, CS2, Na2S
(a)Give two general properties of ionic compounds and two those of covalent compounds.
(b) State one test by which sodium chloride can be distinguished from sugar.
(a)Covalent compounds have generally low melting points.
(b)Ionic compounds have generally high melting points.
(a)What is an ion? Explain with examples.
(b)What is the nature of charge on (i) a cation, and (ii) an anion?
(c)Name the cation and anion present in MgCl2. Also write their symbols.
Explain why, a solution of cane sugar does not conduct electricity but a solution of common salt is a good conductor of electricity.
(a)What is a covalent bond? What type of bond exists in (i) CCl4, and (ii) CaCl2?
(b)What is an ionic bond? What type of bond is present in oxygen molecule?
Fill in the blanks in the following sentences:
(i)Two atoms of the same element combine to form a molecule. The bond between them is known as _____ bond.
(ii) Two chlorine atoms combine to form a molecule. The bond between them is known as _____.
(iii) In forming oxygen molecule, _____ electrons are shared by each atom of oxygen.
(iv) In forming N2 molecule, _____ electrons are shared by each atom of nitrogen.
(v) The number of single covalent bonds in C2H2 molecule are _____.
(vi) Melting points and boiling points of ionic compounds are generally _____ than those of covalent compounds.
Give one example each of the following:
(i)A molecule containing a single covalent bond
(ii)A molecule containing a double covalent bond
(iii)A molecule containing a triple covalent bond
(iv)A compound containing an ionic bond
Which of the following compounds are ionic and which are covalent?
Urea, Cane sugar, Hydrogen chloride, Sodium chloride, Ammonium chloride, Carbon tetrachloride, Ammonia, alcohol, Magnesium chloride.
Which inert gas electron configuration do the Cl atoms in Cl2 molecule resemble? What is this electron configuration?
(a)What type of chemical bond is present in chlorine molecule? Explain your answer.
(b)Explain the formation of a chlorine molecule on the basis of electron theory of valency.
State one major difference between covalent and ionic bonds and give one example each of covalent and ionic compounds.
What type of bonds are present in the following molecules? Draw their electron-dot structures.
(i) H2 (ii) CH4 (iii) Cl2 (iv) O2
Using electron-dot diagrams which show only the outermost shell electrons, show how a molecule of oxygen, O2, is formed from two oxygen atoms. What is the name given to this type of bonding?
(At. No.of Oxygen=8)
One of the following contains a double bond as well as single bomds. This is:
Which of the following has a triple bond as well as single bonds?
A covalent molecule having a double bond between its atom is:
One of the following compounds is not ionic in nature. This compound is:
(a) Lithium chloride
(b) Ammonium chloride
(c) Calcium chloride
(d) Carbon tetrachloride
If the number of protons in one atom of an element Y is 20, then the number of electron in its ion Y2+ will be:
The number of protons in one atom of an element X is 8. What will be the number of electrons in its ion X2-?
The number of protons in the nucleus of one atom of an element Y is 5. The symbol of ion formed by an atom of this element will be:
Out of KCl, HCl, CCl4 and NaCl, the compounds which are not ionic are:
(a) KCl and HCl
(b) HCl and CCl4
(c) CCl4 and NaCl
(d) KCl and CCl4
The atomic number of an element X is 19. The number of electron in its ion X+ will be:
The rechargeable battery used in mobile phone hand set is usually:
(a) Lead ion battery
(b) Sodium ion battery
(c) Hydrogen ion battery
(d) Lithium ion battery
The electrons present in the valence shell of a noble gas atom can be:
(a) 8 only
(b) 2 only
(c) 8 or 2
(d) 8 or 4
Which one of the following property is generally not exhibited by ionic compounds?
(a) Solubility in water
(b) Electrical conductivity in solid state
(c) High melting and boiling points
(d) Electrical conductivity in molten state
Draw the electron-dot structures of the following compounds and state the type of bonding in each case:
The solution of one of the following compound will not conduct electricity. This compound is:
The electronic configuration of three elements X,Y and Z are:
X:32 Y: 2,8,7 Z: 2,8,2
Which of the following is correct regarding these elements ?
(a) X is a metal
(b) Y is a metal
(c) Z is a non-metal
(d) Y is a non-metal and Z is a metal
The atomic numbers of four elements PQ,R and S are 6,10,12 and 17 respectively. Which two elements can combine to form covalent compounds ?
(a) P and R
(b) Q and S
(c) P and S
(d) R and S
The atomic numbers of four elements A,B,C and D are 6,8,10 and 12 respectively. The two elements which can react to form ionic bonds (or ionic compounds) are;
(a) A and D
(b) B and C
(c) A and C
(d) B and D
(a) Write down the electron arrangement in (i) a magnesium atom, and (ii) a chlorine atom.
(b) How many electrons are there in the valence shell of (i) a magnesium atom, and (ii) a chlorine atom.
(c) Show the formation of magnesium chloride from magnesium and chlorine by the transfer of electrons.
(d) State whether magnesium chloride will conduct electricity or not. Give reason for your answer.
(e) Why are covalent compounds generally poor conductors of electricity?
The atomic number of an element X is 16. The symbol of ion formed by an atom of this element will be :
(a) What is the electronic configuration of (i) a sodium atom, and (ii) an oxygen atom?
(b) What is the number of outermost electrons in (i) a sodium atom, and (ii) an oxygen atom?
(c) Show the formation of Na2O by the transfer of electrons between the combining atoms.
(d) Why are ionic compounds usually hard?
(e) How is it that ionic compounds in the solid state do not conduct electricity but they do so when in molten state?
a) Write down the electronic configuration of (i) sodium atom, and (ii) chlorine atom.
(b) How many electrons are there in the outermost shell of (i) a sodium atom, and (ii) a chlorine atom?
(c) Show the formation of NaCl from sodium and chlorine atoms by the transfer of electron(s).
(d) Why has sodium chloride a high melting point?
(e) Name the anode and the cathode used in the electrolytic refining of impure copper metal.
Explain why, a salt which does not conduct electricity in the solid state becomes a good conductor in molten state.
(a) Write the electron arrangement in (i) a magnesium atom, and (ii) an oxygen atom.
(b) How many electrons are there in the valence shell of (i) a magnesium atom, and (ii) an oxygen atom.
(c) Show on a diagram the transfer of electrons between the atoms in the formation of MgO.
(d) Name the solvent in which ionic compounds are generally soluble.
(e) Why are aqueous solutions of ionic compounds able to conduct electricity?
Fill in the following blanks with suitable words:
(a) The corrosion of iron is called _______.
(b) _______ and _______ are necessary for the rusting of iron.
(c) The process of depositing a thin layer of zinc on iron articles is called _______.
(d) Tiffin boxes are electroplated with _______ but car bumpers are electroplated with _______ to protect them from rusting.
(e) The corrosion of copper produces a _______ coating of basic copper carbonate on its surface.
(j) Brass is an alloy of copper and _______.
(g) Bronze is an alloy of copper and _______.
(h) The non-metal present in steel is _______.
(i) The alloy in which one of the metals is mercury is called an _______.
(j) The electrical conductivity and melting point of an alloy is _______ than that of pure metals.
(k) The rocky material found with ores is called _______.
Name one metal each which is extracted by:
(a) reduction with carbon (b) electrolytic reduction
(c) reduction with aluminium (d) reduction with heat alone
Silver metal does not combine easily with oxygen but silver jewellery tarnishes after some time. How?
The atomic number of an element Y is 17. The number of electrons in its Y– will be:
(a) Name the method by which aluminium metal is extracted.
(b) Give the name and chemical formula of one ore of copper.
(c) How is zinc extracted from its carbonate ore (calamine)? Explain with equations.
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Describe with one example, how moderately reactive metals (which are in the middle of reactivity series) are extracted.
How does the method used for extracting a metal from its ore depend on the metal’s position in the reactivity series? Explain with examples.
(a) Name two metals which occur in nature in free state as well as in combined state.
(b) Name one ore of manganese. Which compound of manganese is present in this ore? Also write its chemical formula.
(c) A zinc ore on heating in air forms sulphur dioxide. Describe briefly any two stages involved in the conversion of this concentrated ore into zinc metal.
(a) Why is an iron grill painted frequently?
(b) Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
(a) Why does aluminium not corrode right through?
(b) What is meant by ‘anodising’ ? Why is it done?
(a) Give reason why copper is used to make hot water tanks but steel (an alloy of iron) is not.
(b) Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.
What is meant by ‘rusting of iron’? With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
(a) What is corrosion?
(b) Name any two metals which do not corrode easily.
(c) What is the corrosion of iron known as?
(d) Explain why, aluminium is a highly reactive metal, still it is used to make utensils for cooking.
Explain how, a reduction reaction of aluminium can be used for welding cracked machine parts of iron. Write a chemical equation for the reaction involved.
(a) Define the terms (i) mineral (ii) ore, and (iii) gangue.
(b) What is meant by the ‘concentration of ore’?
(c) Name one ore of copper (other than cuprite). Which compound of copper is present in this ore? Also, write its chemical formula.
(a) What is an alloy? How is an alloy made?
(b) What elements are present in steel? How are the properties of steel different from those of pure iron?
(c) Give the constituents and one use of brass.
Explain giving equation, what happens when:
(a) ZnCO3 is heated in the absence of air?
(b) a mixture of Cu2O and Cu2S is heated?
A sulphide ore is converted into metal oxide by the process of:
Zinc blende ore can be converted into zinc oxide by the process of
The metal which can be extracted from pyrolusite ore is:
The articles made of silver metal become dark on prolonged exposure to air. This is due to the formation of layer of its:
Which of the following metals are extracted by the electrolysis of their molten chlorides?
(a) Na and Hg
(b) Hg and Mg
(c) Na and Mg
(d) Cu and Fe
During galvanisation, iron metal is given a thin coating of one of the following metals. This metal is:
The metal which can be extracted simply by heating the cinnabar ore in air is:
Manganese metal is extracted from manganese dioxide by a reduction process by making use of:
The metal which is always present in an amalgam is:
Which of the following metals can be obtained from haematite ore?
Which of the following alloys contains non-metal as one of the constituents?
Which of the following reactants are used to carry out the themite reaction required for welding the broken railway tracks ?
(a) Al2O3 + Fe
(b) MnO2 + Al
(c) Fe2O3 + Al
(d) Cu2O + Fe
Which of the following pair of metals exist in their native state in nature?
(a) Ag and Hg
(b) Ag and Zn
(c) Au and Hg
(d) Au and Ag
Calamine ore can be used to extract one of the following metals. This metal is:
Which of the following is an ore of mercury metal ?
(a) Rock salt
Which of the following alloys contains mercury as one of the constituents ?
(a) Stainless steel
(d) Zinc amalgam
If copper is kept exposed to dump air for a considerable time, it gets a green coating on its surface. This is due to the formation of:
(a) Hydrated copper sulphate
(b) Copper oxide
(c) Basic copper carbonate
(d) Copper nitrate
In stainless steel alloy, Iron metal is mixed with
(a) Cu and Cr
(b) Cr and Ni
(c) Cr and Sn
(d) Cu and Ni
How are metals refined by the electrolytic process? Describe the electrolytic refining of copper with the help of a neat labeled diagram.
The two metals which are extracted by means of electrolytic reduction of their molten salts are:
(a) Magnesium and manganese
(b) Iron an aluminium
(c) Zinc and magnesium
(d) Magnesium and aluminium.
A common metal which is highly resistant to corrosion is:
The two metals which can be extracted just by heating the sulphides in air are:
(a) Sodium and copper
(b) Copper and aluminium
(c) Potassium and zinc
(d) Mercury and copper
a) Which metal is extracted from calamine ore?
(b) Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.(c) How is copper extracted from its sulphide ore (copper glance), Cu2S ? Explain with equations of the reactions involved.
(d) What is an alloy? Give two examples of alloys.
(e) How are the properties of an alloy different from those of the constituent elements?
a) Name the metal which is extracted from the ore called ‘rock salt’.
(b) Name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae.
(c) Explain how, mercury is extracted from its sulphide are (cinnabar). Give equations of the reactions involved.
(d) In the electrolytic refining of a metal M, what would you take as anode, cathode and electrolyte?
(e) Name any five metals which are purified by electrolytic refining method.
a) Which metal is extracted from bauxite ore?
(b) Give the name of one ore of iron. Which iron compound is present in this ore? Write its chemical formula.
(c) Describe the extraction of zinc metal from its sulphide ore (zinc blende). Write equations of the reactions involved.
(d) Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
(e) Name a common metal which is highly resistant to corrosion.
a) What is the difference between a mineral and an ore?
(b) Which metal is extracted from cinnabar ore?
(c) Name one ore of sodium. Name the sodium compound present in this ore and write its chemical formula.
(d) How is sodium metal extracted? Explain with the help of equation of the reaction involved.
(e) Name three other metals which are extracted in a manner similar to sodium.
(a) Name two metals which are found in nature mainly in the free state (as metallic elements).
(b) Name two metals which are always found in combined state.
(c) What iron compound is present in haematite ore? Also write its chemical formula.
(a) Name the chemical compound which is electrolysed in molten state to obtain aluminium metal. Which gas is evolved during this process?
(b) Name the chemical compound which is electrolysed in molten state to obtain sodium metal. Which gas is produced in this process ?
(c) Name the gas produced when calamine ore is calcined.
(d) Name the gas evolved when cinnabar ore is roasted.
(a) For the reduction of a metal oxide, suggest a reducing agent other than carbon.
(b) Explain why, an aqueous solution of sodium chloride is not used for the electrolytic extraction of sodium metal.
(a) How does the painting of an iron object prevent its rusting?
(b) How does the electrical conductivity of copper alloys, brass and bronze, differ from that of pure copper?
(c) What is meant by 22 carat gold? Name the metals which are usually alloyed with gold to make it harder.
(a) Name an alloy of copper. State its chemical composition and any one use.
(b) Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as ?
(a) Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
(b) Name five methods of preventing rusting of iron.
(c) What are the constituents of stainless steel? What are the special properties of stainless steel?
Which one of the methods given in column I is applied for the extraction of each of the metals given in column II:
|Column 1||Column 2|
|Reduction with carbon||Sodium|
|Reduction with aluminium||Iron|
Calamine ore can be converted into zinc oxide by the process of:
Element X reacts with element Y to form a compound Z. During the formation of compound Z atoms of X lose one electron each whereas atoms of Y gain one electron each. Which of the following property is not shown by compound Z?
(a) High melting point
(b) Low melting point
(c) Occurrence as solid
(d) Conduction of electricity in molten state.
The molecules having triple bond in them are:
(a) Oxygen and ethyne
(b) Carbon dioxide and ammonia
(c) Methane and ethane
(d) Nitrogen and ethyne
What is meant by refining of a metal? Name the most widely used method for the refining of impure metals obtained by various reduction processes. Describe this method with the help of a labelled diagram by taking the example of any metal.
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