Explanation

• The 100 percent pure gold is 24-carat gold.
• Lower cartages contain less gold 18-carat gold contains 75 percent gold and 25 per cent other metals, often copper or silver.
• Carat is the unit of measurement for the physical weight of diamonds/gold.

Last verified on 02-04-2026

Explanation

• Protons and neutrons form the nucleus of an atom.
• Together, they are called nucleons because they are nuclear particles.

Additional information:

• Nucleons determine the mass of an atom.
• Isotopes are atoms of the same element with different number of neutrons.

Last verified on 07-03-2026

Explanation

A mixture of two or more metals (or a metal with non-metals) is called an alloy

An alloy is made by mixing metals.

It improves strength and durability.

Steel (iron and carbon), is an example of an alloy.

Explanation

Good conductors of electricity:-

gold,

silver,

copper,

aluminum,

and graphite.

***

Bad conductors of electricity:-

plastic,

rubber,

glass,

air,

wood,

charcoal,

and diamond.

ND_16_7_2023

Explanation

Iron is the metal with the highest percentage in stainless steel

Iron (Fe):

The foundational element, providing the main structure, usually 60-75%.

Chromium (Cr):

Essential for rust resistance, forming a protective passive layer, typically 10.5% to 30%.

Nickel (Ni):

Added to enhance ductility, strength, and corrosion resistance, especially in austenitic grades (like 304 stainless steel, which has 8% nickel).

Carbon (C):

A small amount (under 1.2%) is present, influencing hardness and other properties. 

Explanation

Explanation

Geologists are scientists who study a planet's solid features, like soil, rocks, and minerals.

Explanation

The neutron is a neutral particle,

which is stable only in the confines of the nucleus of the atom.

Explanation

Stainless steel has the best corrosion resistance property. 

Stainless steel:

Due to its high chromium content, stainless steel forms a protective oxide layer on its surface when exposed to oxygen, significantly resisting corrosion. 

Aluminum steel:

While aluminum also forms a protective oxide layer, it is not as resistant to corrosion as stainless steel. 

Carbon steel:

Carbon steel lacks sufficient chromium and is highly susceptible to rusting. 

Explanation

Sodium is a chemical element with the symbol Na and atomic number 11.

It is a soft, silvery-white, highly reactive metal.

Sodium is an alkali metal, being in group 1 of the periodic table.