## Chemistry (Objective) (Pages :45) <<< Back

• 91 The most abundant element in the universe?

Ans : Hydrogen
• 92 The second most abundant element in the universe?

Ans : Helium
• 93 The only radio active element in liquid form?

Ans : Francium
• 94 The only radio active element in gaseous form?

• 95 The most electro positive stable element?

Ans : Cesium
• 96 The combination of two or more elements . is called?

Ans : Compounds
• 97 The separation of a compound into its elements by chemical means is called?

Ans : Analysis
• 98 The formation of a compound by the union ; of elements is called?

Ans : Synthesis Examples: Water; Steam; Salt etc. .
• 99 The recently discovered chemical compound for the treatment of cancer?

Ans : Cisplatin
• 100 The element which forms largest number of compounds?

Ans : Carbon
• 101 The second element which forms largest number of compounds?

Ans : Hydrogen
• 102 Two or more substances (elements or compounds or both) that do not combine chemically during the mixing?

Ans : Mixtures
• 103 The two kinds of mixtures are:?

Ans : Heterogeneous mixture and Homogeneous mixture
• 104 A mixture of two faces of the matter is called?

Ans : Colloid Eg : Emulsion; Aerosols; Fog; Mt1k
• 105 A colloidal solution formed between two liquids is called?

Ans : Emulsion
• 106 A colloid formed between gas particles and liquid or solid particles?

Ans : Foam
• 107 Colloid which contains particles of liquid or solid dispersed in gas?

Ans : Aerosol
• 108 Atoms of the same element having same atomic number and different mass number are known as?

Ans : Isotopes
• 109 Isotope was discovered by?

Ans : Frederick Soddy
• 110 Which isotope is used to determine the age of fossils ?

Ans : Carbon 14 $• 111 Which isotope is used for the treatment of cancer ? Ans : Cobalt60$
• 112 Which isotope is used for the treatment of skin cancer ?

Ans : Phosphorous 32
• 113 Which isotopes are used as medicine?

Ans : Oxygen 15; Iodine - 131
• 114 Isotopes differ in the number of?

Ans : Neutrons
• 115 The isotopes of hydrogen are?

Ans : Protium; Deuterium; Tritium
• 116 Elements having same mass number and different atomic number are known as?

Ans : Isobars Eg: calcium – 40; Argon - 40
• 117 The term Isobars was suggested by?

Ans : Alfred Walter Stewart
• 118 Atoms of elements having same number of neutrons are called?

Ans : Isotones eg : Helium
• 119 The term Isotones was formed by?

Ans : K.Guggenheimer
• 120 Compounds with same molecular formula but different structures are known as?

Ans : Isomers Eg: Glucose

"Reality is that which, when you stop believing in it, doesn't go away"

- Philip K. Dick