Chemistry work-sheet for class 9
Chapter: The periodic table
One word answer:
A. Answer the following.
i)Element having the smallest size in the periodic table.
ii)Element which is most metallic
iii)Element with highest electron affinity.
iv)Element with highest electronegativity
v)Element with highest ionization energy.
vi)Special name given to group 17 elements.
vii)The longest period
viii)Noble gas having duplet configuration of electrons
ix)Formula of hydride of a halogen in the period3
x)The periodic property which relates to the amount of energy required to remove electron from the outer most shell of an isolated gaseous The atom.
xi)Halogen which is liquid at room temperature.
xii)Halogen which forms violet vapours on heating.
xiii)The periodic property which relates to the ability to attract the shared pair of electrons towards itself.
xiv)An alkali metal stored under kerosene.
xv)An element which has four valence electrons and possess the ability to catenate.
xvi)An element having five valence electrons and is used for packing food material.
xvii)A transition metal which undergoes maximum corrosion
xviii)An element having largest size.
B . Fill in the blanks:
i)Halogens have high ------
ii)Noble gases have zero ------
iii)Fluorine has the highest ------in the periodic table.
iv)Metals form ------chlorides
v)------oxides react both with acids as well as with bases to form salt and water.
vi)As we move across the periodic table metallic character ------
vii)If the element has seven valence electrons it is likely to be a ------.
viii)Across a period ,the ionization potential ------.
ix)Down the group ,electron affinity ------.
x)The horizontal rows in a periodic table are called ------
xi)The properties of the elements are a periodc function of their ------.
xii)A group of elements whose oxides react with water to form strong alkalis is ------.
C. Answer the following questions:
i) How do the following properties change in the alkali metals?
a) Atomic size
b) Metallic character
c) Ionisation potential
d) Electron affinity
as we move from top to bottom in group 1 of alkali metals.
ii) Arrange the elements of group 17 ( At ,F,Br,Cl and I) according to the given conditions.
a)Increasing atomic size
b)Increasing non-metallic character
c)Increasing ionization potential
d)Increasing electron affinity
e)Decreasing electronegativity.
iii) Name any four periodic properties and define those properties.
iv) What is the cause of periodicity?
v) What is Modern Periodic Law?
vi) Write 3 contributions made by Mendeleev?
vii) Write three defects of Mendeleev’s Periodic table.
viii) What is Dobereiner’striad?Give one example.
ix) Explain Newland’s Law of Octaves with suitable example.
x) Explain why reducing power of elements increases as one goes down a group?
xi) How many elements are there in 1st ,2nd and 3rd period of the periodic table?
Xii) The electronic configuration of an element T is 2,8,7.
a)What is the group number of T?
b)What is the period number of T?
c)What is the valency of T?
d)Is T a metal or a non-metal?
e)How many valence electrons are there in an atom of T?
…………………………………x……………0………………..x…………………….
Chapter 2: Chemical bonding(10th class)
- Give reasons:
i)Pure HCl is a bad conductor of electricity.
ii)CCl4 is insoluble in water
iii)Solution of cane sugar does not conduct electricity.
iv)H+ is known as proton.
v)Ionic compounds are solids with high melting points.
vi)Solid ionic compounds do not conduct electricity but their water solution do.
vii)Why do atoms combine.
viii)Why is atom electrically neutral.
- Match the following
Column A Column B
i)Sodium chloride a) increases
ii)Ammonium ion b) Covalent bond
iii) electronegativity
across the period c) ionic bond
iv) non-metallic character d) covalent and co-ordinate down the group
v) Carbon tetrachloride e) decreases
c. One-word answer:
i) A compound which contains all the three types of bonds i.e ionic ,covalent and co-ordinate.
ii) A compound having one lone pair of electrons.
iii) The capacity of an atom to attract the shared pair of electrons towards itself.
iv)A polar covalent compound
v) A non-polar covalent compound
vi) A gaseous molecule containing single covalent bond.
V) A vital gas which contains double bond.
vi) An inert gas which contains triple bond.
vii) A regular tetrahedral molecule
viii)A molecule with one lone pair and three bond pairs.
Ix) Formula of the compound formed between aluminium and oxygen
x)A covalent molecule which on dissolving form ions.
xi)A bond formed by transfer of electrons.
xii)A compound in which shared pair of electrons are equally distributed between the reacting atoms.
xiii)Additional bonding present in water molecules
xiv)A regular tetrahedral molecule.
D. i) On the basis of the knowledge of electronic configuration of elements ,predict the nature of bonds on each of the following molecules.
N2 , CO2, HCl(g) , MgCl2, CCl4, HCN
ii) An element Z is in second period and group 16 of the periodic table .
a)Is it a metal or non-metal?
b)What is the number of valence electrons in its atom?
c)What is its valency?
d)What will be the formula of the compound of Z with sodium?
e)What is the name of the element?
iii) An element A belongs to the third period and group 1 of the periodic table. Find out :
a)The number of valence electrons in its atom.
b)Valency of the element
c)Metal or non-metal
d)Name of the family to which this element belongs and
e)Name of the element.
iv) An element X belongs to the group 2 and another element Y belongs to group 15 of the periodic table.
a)What is the number of valence electrons in X ?
b)What is the valency of X?
c)What is the number of valence electrons in Y?
d)What is the valency of Y?
v) Fill up the blanks :
Across the period: I) Atomic size ------,due to the increased------.
2) Electronegativity character ------,as the tendency to gain electrons ------.
3) Ionisation potential ------,because electrons are held------.
4) Electron affinity ------,because of increased------.
5) Electronegativity ------as the tendency to accept electrons------.
vi) Define the following terms -1) Ionisation energy
2) Electron affinity
3) Electronegativity
4) Covalency
5) electrovalency
6) Co-ordinate bond
The Hyderabad Public School, Begumpet
WORK SHEET
CLASS: 9SUB: CHEMISTRY CHAPTER 2 : STUDY OF GAS LAWS
I
1.Write the value of a)Standard temperature in i) 0Cii)K
b)Standard pressure in i) atmii)mm of Hgiii)cm of Hgiv) torr
2.Convert the followingi)37K to 0C
ii)-27 0C to K
3.Name the law illustrated by a)PV=K ______b)V/T = ______.
4.Mathematical equation for Boyle’s law is ______, Charles law is ______and
gas equation is ______.
5.At a constant temperature, the volume of a gas was found to be 400cm3 at a pressure of 760mm of Hg. If the pressure of the gas is increased by 25%, find the new volume .
6.A certain volume of a gas is under a pressure of 900mm of Hg. When the pressure is increased by 200mm, the gas occupies 2700ml. If this change occurs at constant temperature, calculate the initial volume of the gas.
7.A given mass of a gas is at a temperature of 130C . When the gas is heated to 950C at a constant pressure, it occupies a volume of 460ml. What is the initial volume of the gas?
8. 64000 litres of a gas at a particular pressure and at -330C is packed in 2000 steel cylinders of 8 litres capacity at 270C. The pressure in each cylinder is 15 atmosphere .What is the original pressure of the gas?
9.To what temperature must a gas at 300K be cooled in order to reduce its volume to 1/3 rd of its original volume, pressure remaining constant.
10.What is Boyle’s law?
11. What is Charles law?
12.What is Absolute scale of temperature? Write the value of Kelvin zero in centigrade.
13. At 00C and 760mm Hg pressure, a gas occupies a volume of 100 cm3. The Kelvin temperature of the gas is increased by one fifth while the pressure is increased one and a half times. Calculate the final volume of the gas.
14. Which will have the greater volume when the gases are compressed at STP
a)1.2 litre N2 at 25 0C and 748mm of Hg.
b)1.25 litre O2 at STP?
The Hyderabad Public School, Begumpet
WORK SHEET
CLASS: 9SUB: CHEMISTRY CHAPTER 4 : LANGUAGE OF CHEMISTRY
1.Write the formulae of the compounds from the given cations and anions. Also give the name of the compound.
Cation / Anion / Formula / NameMn+4 / O-2
Ca+2 / HCO3¯
NH4+ / SO4-2
K+ / Cr2O7-2
Na+ / CH3COO-1
2.Write the balanced chemical equations for the following reactions.
a)Potassium bicarbonate + sulphuric acid →potassium sulphate + carbon dioxide + water
b)Ammonia +oxygen → nitric oxide + water
c)Potassium permanganate +HCl → potassium chloride + manganese chloride + chlorine+ water.
d)Silver nitrate → silver + nitrogen dioxide + oxygen
e) Sulphur + nitric acid → sulphuric acid +nitrogen dioxide + water
Q.3)Give the valency and the formula of the following radicals: (1mark each)
a)Chlorate b)Oxalate c)Zincate d)Silicate e)Phosphate f)Nitride g)Cupric
Q4).Write the name of the following molecular formula: (5)
i)K2MnO4 ii) Al2(CO3)3 iii) (CH3COO) 2Pb iv) Na2SiO3 iv) MgSO4
Q5.Complete the following table
Chloride / Nitrate / Sulphate / Carbonate / Hydroxide / PhosphateMagnesium / MgCl2 / Mg(NO3)2 / MgSO4 / MgCO3 / Mg(OH)2 / Mg3(PO4)2
Sodium
Zinc
Silver
Ammonium
Calcium
Iron(II)
Potassium
Q6. Write the valency of : i) nitrogen in N2O ii) Sulphur in SF6
iii)Fluorine in CaF2 iv)Manganese in KMnO4
Q7).Write the chemical formulae of the following compounds: (5)
i) Barium bicarbonate ii) Ferric phosphate iii) Silver(II) sulphide
iv)Ammonium acetate v) Lead bromide.
Q8). Write the formulae and valency of the following radicals: (5)
i) Aluminate ii) Nitride iii) Phosphate iv) Peroxide v) Sulphite.
Q9 a) An element ‘X’ is trivalent .State the formula of its i) sulphate ii) hydroxide ( 2+2)
b) Why should an equation be balanced?
Q10. A metal M forms a carbonate having the following formula M2 (CO3) 3. (2)
i) What is the valency of M?
ii) What will be the formula of fluoride of M?
11. Define i) Radical ii) Variable valency (2marks each)
iii) Chemical formula iv) Balanced equation
Q12. CaCO3 + 2HCl (dil) ------CaCl2 +H2O +CO2(g) (3+3)
i) State the information provided by the above chemical equation.
ii)State the information not conveyed by the above chemical equation.
Q13.Balance the following equations : ( 5x2)
i) Pb3O4 + HCl ------ PbCl2 +H2O + Cl2
ii)NH3 +O2 ------ NO + H2O
iii)ZnS + O2 ------ ZnO +SO2
iv) S + H2SO4 (Conc.) ------SO2 + H2O
V) KOH + Cl2 -----KCl + KClO +H2O
Q14.Balance the following equations: (5x2)
a) Cu + H2SO4 ------ Cu SO4 + H20 + SO2
b) C + HNO3 ------ CO2 + NO2 + SO2
c) H2 S + SO2 ------ S + H2O
d) Fe + H2O ----- Fe3O4 + H2
e) NH3 + O2 ------ NO + H2O
Q 15 Fill in the blanks: (5 marks)
i)Positive radical are called ------radicals.
ii)Chloride, bromide and Iodide are ------radical.
iii)------radical is a basic radical although it is not a metal.
iv)The formula of magnesium nitride is------.
v)Formulae are made by ------method.
Q16. A. Write the following answers in pairs :
Name of the compound Formula (5)
i)Sodium hypochlorite NaNO2
ii)Sodium Chlorate NaClO
iii)Sodium nitrite NaHSO4
iv) Sodium silicate NaClO3
v)Sodium bisulphate Na2SiO3
B. Define 1)Valency 2) Radicals (2)
C.Balance the following:
(4)
i) CuO + NH3 ------ Cu + H2O + N2
ii) NaOH + Cl2 ------ NaCl + NaClO + H2O
iii) ZnS + O2 ------ZnO + SO2
iv) HNO3 ------ H2O + NO2 +O2
ATOMIC STRUCTURE
Q1.A)The composition of two atoms P and Q is given below in this table:
P / 13 / 11 / 11Q / 12 / 11 / 11
i)What is the mass no. of P and Q?
ii)How are Pand Q related to each other?
iii)Which element do these elements represent and give its electronic configuration?
B.Three elements P,Q and R have atomic numbers 4,12 and 20 respectively:
1)State the number of valence electrons in each of the elements.
2)Are these elements going to have similar or different chemical properties?
3) Are these elements metals or non-metals ?
i)Name an element which has two valence electrons ,but is a noble gas.
C)i)Ordinary Chlorine gas has two isotopes 35Cl17 and 37Cl17 in the ratio of 3:1.Calculate the relative atomic number of Chlorine.
ii)Why isotopes of an element have similar chemical properties but different physical properties.
Q4.A)Two elements Magnesium and Nitrogen having atomic numbers 12 and 7:
a)Which of the above elements will donate electron and write the charge and symbol of the ion.
b)Which of the above elements will accept electron and write the charge and symbol of the ion.
c)Name the compound formed by the above elements and write the chemical formula.
Q5. i) 24Mg12 and 26 Mg12are the symbols of magnesium .
Compare the atoms of these isotopes with respect to—
-a)the composition of their nuclei
b)their electronic configurations.
c)give the reason why the two isotopes of magnesium have different mass numbers.
ii) Elememts X,Y,Z have atomic numbers 6,9,12 respectively .Which one:
a)forms anion b)forms Cation c)has four electrons in the outermost orbit. Give reasons.
Q6.i)Write the number of protons and neutrons in the atom of Phosphorous whose atomic no. is 15 and mass no. is 31.
ii)Write the names of three isotopes of Hydrogen and give its symbolic representation.
Q7. i)State the observations when a) Pb(NO3)2 b) Zn CO3 is heated .
------X------O------X------.