Advertisements
Advertisements
Match the non-metallic elements – with their correct symbols. Non-metallic elements are:
| Non-Metallic elements | Symbol |
| (a) Carbon | (1) O |
| (b) Chlorine | (2) I |
| (c) Oxygen | (3) Si |
| (d) Phosphorus | (4) C |
| (e) Hydrogen | (5) Cl |
| (f) Nitrogen | (6) P |
| (g) Iodine | (7) F |
| (h) Bromine | (8) H |
| (i) Fluorine | (9) S |
| (j) Silicon | (10) Br |
| (k) Sulphur | (11) N |
Concept: undefined >> undefined
Match the noble gases – with their correct symbols:
| Noble gases | Symbols |
| (a) Helium | (1) Ar |
| (b) Neon | (2) Xe |
| (c) Argon | (3) Rn |
| (d) Krypton | (4) He |
| (e) Xenon | (5) Kr |
| (f) Radon | (6) Ne |
Concept: undefined >> undefined
Advertisements
Give a reason why elements are tabulated in a table called the ‘Periodic table’.
Concept: undefined >> undefined
Give the names and symbols of the first twenty elements of the periodic table.
Concept: undefined >> undefined
Explain the terms ‘chemical formula’.
Concept: undefined >> undefined
State what a chemical formula denotes.
Concept: undefined >> undefined
Give the symbol and the number of atoms of the following elements present in sodium chloride.
Concept: undefined >> undefined
Give the symbol and the number of atoms of the following elements present in water.
Concept: undefined >> undefined
Give the symbol and the number of atoms of the following elements present in carbon dioxide.
Concept: undefined >> undefined
Give the symbol and the number of atoms of the following elements present in zinc chloride.
Concept: undefined >> undefined
For writing a chemical formula – ‘symbols’ and combining capacity of an element with hydrogen i.e. ‘valency’ should be known. Explain the term – combining the capacity of an element i.e. valency.
Concept: undefined >> undefined
Match the symbols of metallic elements – with their correct combining power or capacity.
(a) K
(b) Zn
(c) Al
(d) Na
(e) Ca
Combining power or capacity – A : 3 ; B : 2 ; C : 1. (positive valencies)
Concept: undefined >> undefined
Match the symbols of non-metallic elements with their correct combining power or capacity.
(a) O
(b) S
(c) Cl
Combining power or capacity A : 3; B : 2; C : 1. (negative valencies)
Concept: undefined >> undefined
Match the symbols of – radicals – with their correct combining power or capacity, (valency).
(a) OH
(b) So4
(c) No3
(d) Co3
Combining power or capacity – A : 3; B : 2; C : 1. (negative valencies)
Concept: undefined >> undefined
Write the formula of the compound formed – given symbols and combining power or capacity (valency) of the following element in the compound.
K1+ Cl1-
Concept: undefined >> undefined
Write the formula of the compound formed – given symbols and combining power or capacity (valency) of the following element in the compound.
Na1+ Cl1-
Concept: undefined >> undefined
Write the formula of the compound formed – given symbols and combining power or capacity (valency) of the following element in the compound.
Ca2+ NO31-
Concept: undefined >> undefined
Match the formulas of the following gases with their correct names :
Gases - (a) H2 (b) N2 (c) O2 (d) Cl2 (e) HCI (f) NH3 (g) CO (h) CO2 (i) SO2 (j) NO (k) NO2.
Names:
(1) Ammonia (2) Nitrogen Dioxide (3) Oxygen (4) Hydrogen (5) Nitrogen (6) Chlorine (7) Carbon Monoxide (8) Sulphur Dioxide (9) Nitrogen Monoxide (10) Carbon Dioxide (11) Hydrogen Chloride
Concept: undefined >> undefined
Match the formulas of the following of acids with their correct names:
Acids – (a) HCI (b) HNO3 (c) H2SO4 (d) H2CO3
Names – (1) Carbonic acid (2) Sulphuric acid (3) Hydrochloric acid (4) Nitric acid
Concept: undefined >> undefined
Match the formulas of the following of bases with their correct names.
Bases – (a) NaOH (b) KOH (c) Ca(OH)2 (d) Zn(OH)2
Names – (1) Potassium hydroxide (2) Zinc hydroxide (3) Aluminium hydroxide (4) Calcium hydroxide (5) Sodium hydroxide
Concept: undefined >> undefined
