Q71. An element which is preserved under water is
[A] red phosphorus
[B] white phosphorus
[C] sodium
[D] sulphur
Q72. Which of the following is not a property of water?
[A] Low specific heat
[B] Low heat of vaporisation
[C] Low density
[D] All of the above
Q73. A pure substance can only be
[A] an element or a compound
[B] Compound
[C] a heterogeneous mixture
[D] an element
Q74. Orlon is a polymer of
[A] Acrylonitrile
[B] Dacron
[C] Polyamide Nylon
[D] None of the above
Q75. Systematic name for (CuI)s ?
[A] Ferrous Oxide
[B] Copper Iodide
[C] Cobalt Fluoride
[D] All of the above
Q76. What is the conjugate base of H2O?
[A] OH-
[B] NH3+
[C] H2O
[D] All the above
Q77. Name the Scientist who stated that matter can be converted into energy
[A] Einstein
[B] Avogadro
[C] Lavoisier
[D] Boyle
Q78. The process of change from liquid to gas is called
[A] Decantation
[B] Condensation
[C] Vaporisation
[D] Precipitation
Q79. Blue litmus paper turns ____________ on contact with an acidic solution.
[A] red
[B] brown
[C] yellow
[D] green
Q80. Who is the father of modern chemistry?
[A] Lavoisier
[B] Dalton
[C] Mendeleeff
[D] Priestley