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प्रश्न
Why do gold ornaments look new even after several years of use?
उत्तर १
Gold is the most unreactive metal, so it does not react with air, water, or other gases in the atmosphere. Therefore, gold does not corrode, which is why it looks new after several years of use.
उत्तर २
Gold, being the least reactive, does not react with atmospheric reagents.
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संबंधित प्रश्न
You are given a hammer, a battery, a bulb, wires and a switch.
- How could you use them to distinguish between samples of metals and non-metals?
- Assess the usefulness of these tests in distinguishing between metals and non-metals.
Give reasons for the following.
Immersion rods for heating liquids are made up of metallic substances.
For the electro-refining of copper: What is the cathode made up of?
Name two metals which are both malleable and ductile.
Choose the acidic oxides, basic oxides and neutral oxides from the following:
Na2O; CO2; CO; SO2; MgO; N2O; H2O.
Which of the following non-metal is a liquid?
(a) carbon
(b) sulphur
(c) bromine
(d) iodine
The electronic configurations of four particles A, B, C and D given below:
| A | 2, 8, 8 |
| B | 2, 8, 2 |
| C | 2, 6 |
| D | 2, 8 |
Which electronic configuration represents:
(i) magnesium atom?
(ii) oxygen atom?
(iii) sodium ion
(iv) chloride ion?
Name a metal that can be cut with knife
Name a metal used in making electric cables
A non-metal A is an important constituent of our food and forms two oxides B and C. Oxide B is toxic whereas C causes global warming
- Identify A, B and C
- To which Group of Periodic Table does A belong?
