How many groups are present in modern periodic table

How many groups are there in the modern periodic table?

Answer the following questions: What is meant by modern periodic table ?

How many skeletal muscles are present in the human body.

Name the following: Horizontal rows in modern periodic table.

In the modern periodic table, the elements are arranged in the increasing order of their atomic number. This arrangement is based on the modern periodic law, which states that the properties of elements are a periodic function of their atomic numbers. In the modern periodic table, each column is called a group and each row is called a period. Elements within the same group show similarity and gradation in properties. This is due to the same number of electroms in the outermost shell . Based on the above paragraph, answer the following question: How many groups are there in the modern periodic table?

How many elements are present in the 6th period? Explain.

How many particles are present in 1 mole of a substance ?

How many polypeptide chains are present in a antibody?

Mendeleev predicted the existence of certain elements not know at that time. He named two of these elements as eka-aluminium and eka-silicon. a. Name the elements which have taken the place of these elements. b. Mention the group and period of these elements in the modern periodic table. c. Which one of these two elements is a metalloid? d. How many valence electrons are present in eka-silicon? e. Eka-aluminium forms a chloride. What is its formula?