Explanation

 The synthetic fiber known as artificial silk is called rayon.

Rayon is a semi-synthetic fiber derived from natural sources like wood pulp

Explanation

Red phosphorus is the form of phosphorus used in safety matches.

It's found on the striking surface of the matchbox, not in the match head itself.

This design separation prevents the match from spontaneously igniting. 

Explanation

Gold is the most malleable metal, which means it can be beaten into thin sheets or shapes without breaking.

Gold is a soft, ductile metal with a high degree of plasticity, making it easy to work with.

It can be hammered, rolled, or bent into various forms without cracking or shattering.

Explanation

Mercury (Hg) is used in thermometers.

Because it expands and contracts consistently with temperature changes.

It providing accurate readings.

It also emits ultraviolet light in fluorescent tubes when electrically excited.

Explanation

Mercury is the only metal that is liquid at room temperature, unlike the others (Copper, Brass, Aluminum, Silver, Titanium, Platinum) which are solid.

It remains in liquid form due to its low melting point of about -38.83°C.

Explanation

Copper is a non-magnetic material, meaning it does not exhibit magnetic properties.

Cobalt, Iron, and Nickel are magnetic materials, as they can be magnetized and attract magnets.

Explanation

Phosphorous, especially red phosphorous, is used in the preparation of matchsticks because it ignites easily due to its rapid burning property.

It helps in the quick ignition of the match when struck.

Explanation

Most abundant element in Earth crust is Oxygen.

Oxygen in the crust is (46.1%).

The chemical formula of oxygen (dioxygen) is O2.

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List of 10 Most Abundant Elements in the Earth's Crust

Explanation

Aluminum is the most abundant metal in the Earth's crust.

It comprising about 8% of its weight.

It is primarily found in the form of bauxite ore.

Explanation

Oxyacetylene flame is used in welding and cutting metals due to its high temperature.

It provides a flame temperature of about 3200°C, making it suitable for industrial applications.