1. When CO2 is bubbled into lime water, a white cloud appears. What is the name of the white precipitate which appears as a cloud in the beginning?
A. CO2
B. CaCO3
C. Mg(OH)2
D. CaCl2
2. A man goes door to door posing as the Goldsmith. He promises to bring back the glitter on dull gold ornaments. An unsuspecting woman gives a set of gold bangles to him which he dips in a particular solution. The bangles sparkle but their weight has considerably reduced. The solution used by the imposer probably is –
A. dil. HCl
B. conc. HCl
C. a mixture of conc. HCl and conc. HNO3
D. conc. HNO3
3. The substance which affect the central nervous system and induce sleep are called –
A. antipyretics
B. analgesics
C. tranquillizers
D. none of these
4. Which of the following is a common antacid?
A. Mg(OH)2
B. Ca(OH)2
C. NaOH
D. KOH
5. A substance which can acts both as an antiseptic and disinfectant is –
A. chloroxylenol
B. phenol
C. aspirin
D. bithional
6. Generally, non-metals are not lustrous. Which of the following non-metal is lustrous?
A. nitrogen
B. oxygen
C. iodine
D. sulphur
7. Generally, metals are solid in nature. Which one of the following metals is found in liquid state at room temperature?
A. Hg
B. Cr
C. Na
D. Fe
8. Galvanization is a method of protecting iron from rusting by coating with a thin layer of –
A. Zinc
B. Aluminium
C. Silver
D. Gallium
9. Silver articles become black on prolonged exposure. This is due to-
A. Ag3N
B. Ag2S and Ag3N
C. Ag2O
D. Ag2S
10. Which one of the following metals does not react with cool water as well as hot water?
A. Mg
B. Na
C. Ca
D. Fe
