Match the following: \(\begin{array}{ll}\text { List I } & \text { List II }\end{array}\) 1\. Nichrome (1) \(\mathrm{Pb}, \mathrm{Bi}, \mathrm{Sn}, \mathrm{Cd}\) 2\. Type metal (2) \(\mathrm{Pb}, \mathrm{Sb}, \mathrm{Sn}\) 3\. Wood's metal (3) \(\mathrm{Cu}, \mathrm{Al}, \mathrm{Zn}\) 4\. Devarda's alloy (4) Fe, Ni, Cr The correct matching is \(\begin{array}{llll}1 & 2 & 3 & 4\end{array}\) (a) (2) (1) (3) (4) (b) (3) (4) (2) (1) (c) (4) (2) (1) (3) (d) (3) (4) (1) (2)

Nichrome is a type of alloy that is best known for its high resistance and ability to withstand high temperatures without corroding. This makes it an ideal material for heating elements in things like toasters, hair dryers, and even industrial furnaces. The main components of nichrome are nickel (Ni) and chromium (Cr), and sometimes it includes iron (Fe) to enhance its properties.

One of the most interesting characteristics of nichrome is its resistance to 'oxidation'. Oxidation is a common problem for metals at high temperatures as it leads to corrosion. Thanks to chromium, nichrome forms an invisible protective layer, often called a 'passive layer', which shields the metal underneath from the air and keeps it from rusting. If you're working on an application that requires durable and stable resistance over time, then nichrome would be a top contender for materials to consider.

Type metal is a distinct type of alloy once widely used in the printing industry, specifically for creating the typefaces used in traditional printing presses. The standard formulation of type metal includes lead (Pb), antimony (Sb), and tin (Sn). The combination of these metals provides a material that's both sturdy and able to cast intricate and clear letters.

Historical Importance of Type Metal

Historically, the introduction of type metal was vital for the spread of written knowledge. Because it was durable yet malleable, it allowed for the mass production of consistent and legible text, contributing significantly to printing technology.
Type metal has a lower melting point than pure lead, making it easier to work with when casting small objects. Its sharp melting point is also beneficial for producing clear and precise castings. Despite its decline in usage due to digital printing techniques, its legacy in the history of printing is invaluable.

Wood's metal is renowned for its low melting point, which makes it valuable for a variety of niche applications, such as in the creation of emergency sprinkler systems and in soldering as a fusible alloy. This alloy mainly contains bismuth (Bi), lead (Pb), tin (Sn), and cadmium (Cd). The low melting point is due to the eutectic nature of the alloy, meaning that its melting point is significantly lower than that of its individual components.

Safe Handling of Wood's Metal

It's important to note that despite its useful properties, Wood's metal contains toxic elements like lead and cadium, and should be handled with care, following proper safety protocols. It's often utilized in a controlled environment such as laboratories or manufacturing processes where safety measures can be strictly enforced.

Devarda's alloy plays a crucial role in analytical chemistry, especially in the qualitative and quantitative analysis of nitrates. This alloy is composed of copper (Cu), aluminum (Al), and zinc (Zn). When used in the reduction of nitrates, it produces ammonia, which can then be detected and measured.

The presence of aluminum is notably significant in Devarda's alloy's reactivity; it acts as a strong reducing agent in reactions. This characteristic is particularly helpful in laboratory processes where it's important to have a predictable and consistent reactive agent. Although not as commonplace as the other alloys mentioned here, Devarda's alloy's specialized function in chemical analysis denotes its importance in scientific methodologies.