Chemical Compounds and Reactions

Silver nitrate (AgNO3) is historically called Lunar Caustic because silver was associated with the moon (luna). It was used as a caustic agent for cautery. The other options are not recognized common names for silver nitrate.

Indian red is ferric oxide (Fe2O3), a naturally occurring red pigment used in paints and dyes. It's not zinc sulfate, ferrous oxide (FeO), or aluminum sulfate - those are completely different compounds. The red color comes from the iron in the +3 oxidation state.

Chromium(II) is Cr2+. Sulfate (SO4) has a -2 charge. They cancel in a 1:1 ratio, giving CrSO4. Cr2SO4 would be Cr4+, and Cr(SO4)2 would require Cr4+.

Silver(I) chloride, also called argentous chloride, has the chemical formula AgCl - formed from silver (Ag) and chlorine (Cl). It's a white insoluble solid sensitive to light. NaOH is sodium hydroxide, HCl is hydrochloric acid, and KBr is potassium bromide.

Different metal salts produce characteristic flame colors in fireworks: barium compounds give green, strontium gives red, copper gives blue, and sodium gives intense yellow. This occurs because the metal atoms absorb energy and release it as specific wavelengths of visible light. Mercury and potassium don't produce green flames in this context.

Excess of nitrates in drinking water causes methaemoglobin formation which results in blue baby syndrome or  methemoglobinemia.

Ammonium dichromate is an inorganic compound with the formula (NH₄)2Cr₂O₇. It is a salt consisting of ammonium ions and dichromate ions. It has been used in pyrotechnics and in the early days of photography as well as in lithography, as a source of pure nitrogen in the laboratory, and as a catalyst.

It reduces acidified potassium dichromate solution to a green-coloured chromic salt.

It decolourises KMnO₄.

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[Al(H₂O)₆]³⁺(aq) is a colourless solution.

Silver Nitrate first reacts with HCl to give white ppt of silver chloride, this silver chloride soluble in excess of ammonium hydroxide to form diamminesiver chloride

When Copper oxide is treated with concentrated hydrochloric acid no gas is evolved but a blue solution is obtained.

MnO₂ and CuO are two black coloured oxidizing agents

It is an acid, which turns litmus red and the chloride ion of hydrochloric acid gives white precipitate with silver nitrate solution.