Question

The three elements having chemical symbols of Si, B and Ge are:
A.All metals
B.All non-metals
C.All metalloids
D.Si is metalloid, B is metal and Ge is non-metal

Answer 1

The elements having chemical symbols of Si (Silicon). B (Boron), and Ge (Germanium) are found in the periodic table from the ${13^{th}}$ to the ${16^{th}}$ group.

Complete step by step answer:
Metalloids are a very small group of elements and they are found in the periodic table of elements along the zig-zag line that differentiates the metals from nonmetals and is drawn from between boron and aluminium to the border between polonium and astatine. These seven elements were classified as metalloids in the periodic table from the ${13^{th}}$ to the ${16^{th}}$ group.
The elements that are considered to be metalloids are Boron (B), Silicon (Si), Germanium (Ge), Arsenic (As), Antimony (Sb), Tellurium (Te) and Polonium (Po)
Si is Silicon and the name silicon derives from the Latin silex or silicas, which means “flint” or “hard stone”. Amorphous elemental silicon was first isolated and described as an element in 1824 by Jon’s Jacob Berzelius, who was a Swedish chemist.
B is Boron and the name boron is derived from the Arabic 'buraq', which was the name for borax. It was discovered by Louis-Josef Gay-Lussac and Louis-Jacques Thénard in Paris, France, and Humphry Davy in London, UK in 1808.
Ge is Germanium and the name germanium derives from the Latin word Germania [Germany] and was given to the element by Winkler. It is a silvery Gray metalloid and is between silicon and tin in Group 14 (IV a) of the periodic table. The existence, properties, and position in the periodic system of Germanium has been predicted in 1871 by the Russian chemist Mendeleyev before it was discovered in 1886 by Clemens Winkler, a German chemist.
Thus, B (Boron), Si (Silicon), Ge (Germanium) are metalloids.

Therefore, the correct answer is option (C).

Note: Silicon and germanium are both semiconductors with structures analogous to diamond. Germanium is a silvery-white semi-metal. It is brittle. Boron is used in fireworks as it has the quality of changing colour into green when it is burnt. It is one of the most explosive metalloids. Silicon in the form of silicones can be used as a waterproof sealant on roofs, around the water pipes. Germanium is used in semiconductor industries to improve the conductive properties.