Dried fruit plastic bags sold in the market are filled with:
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Cryolite is used in the electrolytic reduction of Alumina (Al2O3) to:
What happen when calcium is treated with water?
A. It does not react with water.
B. It reacts violently with water.
C. It reacts less violently with water.
D. Bubbles of hydrogen gas formed during the reaction stick to the surface of calcium.
The following metals exist in their native state:
P4+NaOH+3H2O→X+3NaH2PO2 What does ‘X’ indicate here?
Which of the following pairs will give displacement reactions?
Which of the following metals are obtained by electrolysis of their chlorides in molten state?
A. Na
B. Ca
C. Fe
D. Cu
2Al+Fe2O3→2Fe+Al2O3+Heat. This reaction is an example of:
Name the metal which is the best conductor of electricity.
Which of the following metal reacts neither with cold water nor with hot water but reacts with hot steam to produce hydrogen gas?
Which of the following property is generally shown by metals?
A. Electrical conduction
B. Sonorous in nature
C. Dullness
D. Ductility
Which process is used for the enrichment of oxide ores?
Name the reducing agent in the following reaction
3MnO2+4Al→3Mn+2Al2O3
Which of the following has electrovalent bond(s)?
A. CaF
B. NaCl
C. MgO
D. CO2
Which of the following alloy is used for joining metals for electrical work?
The Iron pillar near the Qutub Minar in Delhi is prevented from rusting because of:
Statement A: All metals form basic oxides.
Statement B: Few non metals form neutral oxides.
Metals are alloyed to:
A. Decrease hardness.
B. Lower melting point.
C. Decrease resistance towards corrosion.
D. Increase tensile strength.
The ratio of HCl and HNO3 in Aqua Regia is:
An element belonging to 16th group of periodic table is used in the manufacturing of vulcanized rubber. This element reacts with hot and conc. HNO3 to form sulphuric acid. The concerned element is:
Which oxide will turn blue litmus solution to red?
A. SO2
B. MgO
C. Na2O
D. NO2
Galvanisation process involves elements zinc and iron. Which of the two metals is sacrificing its life to save the life of the other?
The group of metals which do not react with oxygen:
Statement A: The electrical conductivity and melting point of an alloy is less than that of pure metals.
Statement B: Different metals have same reactivity with water and dilute acids.
Iron pillar at Delhi is made up of:
Which one of the following is not a method for enrichment of an ore?