Fill in the blanks.1) A proton has_charge.2)Q.8.13is the atomic number of calcium.3) Total number of periods and groups in the modern periodic table areQ.9.Answer the following questions.1) What are valence electrons? How many valence electrons are there in nitroge2) Write the electronic configuration of Aluminium and Sodium.

Fill in the blanks.1) A proton has_charge.2)Q.8.13is the atomic number

1.	Fill in the blanks.1) A proton has_charge.2)Q.8.13is the atomic number of calcium.3) Total number of periods and groups in the modern periodic table areQ.9.Answer the following questions.1) What are valence electrons? How many valence electrons are there in nitroge2) Write the electronic configuration of Aluminium and Sodium.
Answer» <p>1.valence electrons are the electrons present in outermost shell of an atom to form a chemical bond. nitrogen has 5 valence electrons. </p> <p>8. 1) A proton has a positive charge. 2) 20 is the atomic number of Calcium. 3) The number of periods is 7 and no of groups is 18 in the modern periodic table.9. 1) Valence electrons are the number of electrons in the outermost shell of an atom. Nitrogen has 5 electrons in its outermost shell. 2) Aluminium(13) electron configuration: 2 8 3 Sodium(11) electron configuration: 2 8 1</p>