Answer the following questions:
How many electrons are there in the outermost shell of group 18 elements?

Answer the following questions: How many electrons are there in the outermost shell of group 2 elements?

Answer the following questions: How many valence electrons are there in the outermost shell of silicon?

Answer the following questions : How many covalent bonds are there in a molecule of cyclohexane?

Answer the following questions: Which group elements have seven electrons in the outermost shell?

Answer the following questions: How many elements are there in the second and the third periods of the periodic table ?

Answer the following questions in one sentence each : How many electrons could there be in the outermost orbit of an element whose valency is 3 ?

Answer the following questions: Whar is meant by valency electron?

Answer the following questions: What is meant by symbol of an element?

Answer the following questions: Depending on electronic configuration the properties of the elements vary in different groups . Explain why ?

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?