periodic table, periodic properties, variations of properties, icse, class-10,

Question

 With reference to the elements of the modern periodic table.

 Fill in the blanks with the appropriate word/s in each case.

1. The element in group 17 [VILA] which is a liquid at room temperature is ...... [F, Cl, Br, I]

2. Periodicity in properties is observed in elements after definite intervals due to similar ........................ [electronic configuration, number of valence electrons, atomic numbers] of elements.

3. Across a period the nature of oxides and hydrides varies from ......to .........while the strength of oxy-acids ......... from left to right.

4. Nuclear charge of an atom is the ........... charge on the nucleus of an atom, equivalent to the atomic .......... of an atom.

5. Atomic size of neon is............ than the atomic size of fluorine.

Answer 1

1. The element in group 17 [VILA] which is a liquid at room temperature is Br [F, Cl, Br, I],

2. Periodicity in properties is observed in elements after definite intervals due to similar Number of Valence electrons [electronic configuration, number of valence electrons, atomic numbers] of elements.

3. Across a period the nature of oxides and hydrides varies from basic to acidic while the strength of oxy-acids increases from left to right. 

4. Nuclear charge of an atom is the positive charge on the nucleus of an atom, equivalent to the atomic number of an atom.

5. Atomic size of neon is more than the atomic size of fluorine.