d. emerald is not an allotrope of carbon
Emerald is not an allotrope of carbon. It is a variety of the mineral beryl, which is a beryllium aluminum silicate. Buckyball, diamond, and graphite are all allotropes of carbon, which means they are different forms of the same element that have different physical and chemical properties.
Here is some more information about other options which will help you understand better :-
a. Buckyball: Buckyball, also known as fullerene or C60, is a molecule composed entirely of carbon. It has a unique structure resembling a soccer ball made up of 60 carbon atoms arranged in a spherical shape with 12 pentagonal and 20 hexagonal faces. Buckyballs are a type of allotrope of carbon, and they have interesting physical and chemical properties that have led to many potential applications in materials science and medicine.
b. Diamond: Diamond is one of the most well-known allotropes of carbon. It is a naturally occurring mineral that is made up of pure carbon atoms arranged in a crystal lattice structure. Diamonds are known for their hardness and high refractive index, which gives them their characteristic sparkle. They are used in jewelry and industrial applications such as cutting and polishing tools.
c. Graphite: Graphite is another allotrope of carbon. It is a soft, black mineral that is made up of layers of carbon atoms arranged in a hexagonal pattern. The layers are held together by weak intermolecular forces, which give graphite its slippery, lubricating properties. Graphite is used in many applications, including as a lubricant, in batteries, and as a material for nuclear reactors.
d. Emerald: Emerald is a green variety of the mineral beryl, which is a beryllium aluminum silicate. It is not an allotrope of carbon. Emeralds are prized gemstones and are used in jewelry. They get their green color from trace amounts of chromium and vanadium in their crystal structure.
