66. Presence of which among the following minerals in Banana makes them slightly radioactive?
A. Sodium
B. Calcium
C. Magnesium
D. Potassium
67. Which of the following is also known as wood alcohol?
A. Methanol
B. Ethanol
C. Propanol
D. Butanol
68. Which of the following represents Reduction?
A. Losing one or more electrons
B. Gaining one or more electrons
C. Losing Hydrogen atoms
D. Liberating hydrogen gas
69. The nuclear particle having no mass and no charge, but only spin is:
A. Proton
B. Neutrino
C. Meson
D. Electron
70. Browning of paper in old books is caused by:
A. frequent use
B. lack of aeration
C. collection of dust
D. oxidation of cellulose