Answer:
The two statements are all True for group 7 and 8 elements.
Explanation:
The Group 7 elements are known as the halogens. They are reactive non-metals and are always found in compounds with other elements. Chlorine, bromine and iodine are all halogens.
Chlorine, bromine and iodine are the three common Group 7 elements. Group 7 elements form salts when they react with metals. The term ‘halogen’ means 'salt former'.
In addition to the discription given to norble gases in the question which is true, norble gases;
- are inert gases located on the right of the periodic table.
- have a full-set of valence electrons, so they're stable, unreactive
- are colorless, odorless and tasteless.
- have low melting and low boiling points.
- can be found in small amounts in the Earth's crust and the Earth's atmosphere.
The average kinetic energy of colliding particles can be increased by increasing temperature.
B.
1-It has to be 3 Fe and not Fe3.
2-The oxygens aren't balanced
Balanced equation:
3Fe+4H2O---->Fe3O4+4H2
Mn metal can be used as a sacrificial electrode to prevent the rusting of an iron pipe. So, the correct option is (c) Mn.
Commonly, sacrificial electrodes are employed to stop another metal from corroding or oxidising. A metal that is more reactive than the metal being shielded must serve as the sacrificial electrode. Magnesium, aluminium, and zinc are the three metals most frequently used in sacrificial anodes.
Manganese-Magnesium (Mn-Mg) electrode is more suited for on-shore pipelines where the electrolyte (soil or water) resistivity is higher since it has the highest negative electropotential of the three. In order to replenish any electrons that could have been lost during the oxidation of the shielded metal, the highly active metal offers its electrons.
Therefore, Mn metal can be used as a sacrificial electrode to prevent the rusting of an iron pipe. So, the correct option is (c) Mn.
Learn more about electrode here:
brainly.com/question/17060277
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