Quiz On Activity Series Of Metal

When copper powder is added to a colorless solution of silver nitrate, it produces a solution of deep color. Copper is a colored metal in the activity series, and silver nitrate is a colorless solution.

All of the given options, gold, platinum, and silver, occur naturally in the activity series. The activity series is a list of metals arranged in order of their reactivity, with the most reactive metal at the top. Gold, platinum, and silver are all noble metals, which means they are very unreactive and occur naturally in their pure form. Therefore, all of the above options are correct as they are naturally occurring metals in the activity series.

Magnesium is the correct answer because it is a highly reactive metal that reacts vigorously with steam to produce magnesium oxide and hydrogen gas. During the reaction, magnesium burns with a dazzling white light, making it useful for various applications like fireworks, flares, and photography. Sodium and potassium are also reactive metals, but they react with water rather than steam to produce their respective oxides and hydrogen gas.

Both sodium and potassium can only be obtained by electrolysis of their fused chlorides. This is because sodium and potassium are highly reactive metals and cannot be obtained by simple reduction methods. Electrolysis of their fused chlorides allows for the extraction of these metals in their pure form. Silver, on the other hand, is not obtained through electrolysis of its fused chloride but rather through other extraction methods such as smelting or chemical reduction.

Sodium is a metal in the activity series whose oxide is highly soluble in water. This means that when sodium oxide (Na2O) is added to water, it readily dissolves and forms sodium hydroxide (NaOH), a strong base. Sodium is highly reactive and belongs to Group 1 of the periodic table, known as the alkali metals. These metals have a strong tendency to react with water, producing alkaline solutions. Therefore, sodium is the correct answer as its oxide is highly soluble in water.

Aluminium and sodium are the two metals whose oxides cannot be reduced by hydrogen. This is because aluminium oxide and sodium oxide are stable compounds that do not easily react with hydrogen to form the respective metals. Aluminium oxide has a strong ionic bond and requires a more powerful reducing agent, such as carbon, to be reduced. Similarly, sodium oxide is a stable compound that requires a stronger reducing agent, like electrolysis or a reactive metal, to be reduced. Therefore, hydrogen gas is not effective in reducing the oxides of aluminium and sodium.

Hydrogen would be placed between copper and lead in the activity series. This means that hydrogen is more reactive than copper but less reactive than lead. The activity series is a list of elements arranged in order of their reactivity, with the most reactive element at the top. Since copper is less reactive than hydrogen, it would be placed before hydrogen in the activity series. Similarly, since lead is more reactive than hydrogen, it would be placed after hydrogen in the activity series. Therefore, hydrogen would be placed between copper and lead.

Gold is a metal in the activity series whose oxide does not occur naturally. This is because gold is a noble metal, which means it is resistant to oxidation and does not readily react with oxygen in the air to form an oxide. Unlike other metals like copper, lead, and aluminium, gold is highly unreactive and does not easily form compounds or react with other elements. Therefore, gold oxide is not naturally found in the environment.

Sodium and potassium are the correct answer because their hydroxides and carbonates are stable to heat. This means that when these compounds are heated, they do not decompose or undergo any significant chemical changes. This stability is due to the strong bonding between the metal ions and the hydroxide or carbonate ions. As a result, sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate can withstand high temperatures without breaking down into their constituent elements or forming new compounds.

When the nitrates of silver and mercury are heated, they decompose to form the respective metals. This is because these metals are higher in the activity series, meaning they are more reactive and have a greater tendency to form compounds. On heating, the nitrates break down, releasing oxygen and leaving behind the pure metal. Sodium and potassium are also high in the activity series, but their nitrates do not give the metals on heating.

Zinc is the correct answer because when zinc oxide is heated, it appears yellow in color. However, when it cools down, it turns white. This phenomenon is due to the change in the crystal structure of zinc oxide at different temperatures.

When nitrates of certain metals are heated, they undergo decomposition to form nitrites. In this case, the correct answer is sodium and potassium. Both sodium nitrate and potassium nitrate decompose upon heating to form sodium nitrite and potassium nitrite respectively.

Lead and zinc are two metals in the activity series that react with steam to give oxides that have acidic and basic properties. When lead reacts with steam, it forms lead(II) oxide (PbO), which is amphoteric and can act as both an acid and a base. When zinc reacts with steam, it forms zinc oxide (ZnO), which is also amphoteric. This means that it can react with both acids and bases, exhibiting both acidic and basic properties. Therefore, the correct answer is lead and zinc.

Calcium is the correct answer because when calcium oxide (CaO) reacts with water, it forms calcium hydroxide (Ca(OH)2), which is sparingly soluble in water. Calcium hydroxide forms a white precipitate when it reacts with water, indicating its low solubility.

Iron cannot displace hydrogen from an alkali because it is less reactive than hydrogen. In a displacement reaction, a more reactive element can displace a less reactive element from its compound. Since iron is less reactive than hydrogen, it cannot displace hydrogen from an alkali.