Elements are classified as metals, non-metals, metalloids and inert gases. Which of them form electrovalent bond ?

Mendeleev predicted the existence of certain elements not known at that time and named two of them as Eka-Silicon and Eka-aluminium (a) Name the elements which have taken the place of these elements (b) Mention the group and the period of these electron in the modern periodic table (c) Classify these elements as metals, non-metals or metalloids (d) How many valence electrons are present in each one of them ?

Which of the following is a non-metal ?

An element X (atomic number 17) reacts with an element Y (atomic number 20) to form a divalent halide (a) Where in the periodic table are elements X and Y placed ? (b) Classify X and Y as metal (s), non-metal (s) or metalloid (s) (c) What will be the nature of oxide of element Y ? Identify the nature of bonding in the compound formed (d) Draw the electron dot structure of the divalent halide.

Name a noble metal and a metalloid.

Give reasons. Inert gases do not form compounds

Which block of elements consists of metals, non metals and metalloids ?

Which of the following elements can be classified as a metalloid ?

Elements showing properties of both metals and non-metals