PERIODIC CLASSIFICATION OF ELEMENTS
TIME: 1:30 hrs. M.M.:50
Questions From 1 to 6 carries 1 marks each.
Questions From 7 to 13 carry 2 marks each.
Questions From 14 to 17 carry 5 marks each.
Questions From 18 to 27 carries 1 marks each.
- What is the position of Hydrogen in the Modern periodic table?
- Where are the isotopes of the same element having different atomic masses placed in the periodic table?
- An element M is in third group of the periodic table. Write the formula of its oxide.
- What is the valency of Magnesium with atomic number 12 and chlorine with atomic number 17?
- What is the difference in number of shells in magnesium and sulphur?
- On the basis of electronic configuration, how will you select:
(i) The terminating member in a period.
(ii) The chemically similar elements.
- Give reason as to why the atomic radii of elements increase in a group while moving from top to bottom?
- Elements in a group of the periodic table have similar chemical properties. Why?
- Explain why atomic number is more important than atomic weight in determining chemical properties?
- Where in period 2 of the periodic table do we find:
(i) Elements classified as non metals.
(ii) Elements forming negative ions
(iii) Elements with high melting points
(iv) Elements forming positive ions
11.In a group reactivity of metals increases while those of non metals decreases when we going a group. Explain.
12.Elements in a group of the periodic table have similar chemical properties. Why?
13.Elements of group 18 are called zero group .why?
14. Write the electronic configuration of atoms of
(a) Potassium (K) (b) Argon (Ar), (c) Lithium (Li), (d) Fluorine (F), (e) Chlorine (Cl).
These have atomic numbers as 19, 18, 3, 9 and17 respectively. Uses the electronic configuration to explain.
(i). Why is potassium more reactive than lithium?
(ii).Why is fluorine more reactive than chlorine?
(iii).Which is smaller in size Cl or Ar?
(iv).Which is smaller in size Li or F?
(v).Which is more electronegative F or Cl?
15. The atomic number of an element is 17.
(i)What is its valency?
(ii)Whether it is a metal or non metal?
(iii).Whether it is bigger or smaller in size than an element of atomic number 18?
(iv).What type of bonds it will form with elements of group 18?
(v). How would its oxide behave with litmus solution?
- An element has two electrons in its M shell:
(a) Identify the element. (b) What type of ion will it form? (c) What will be the formula of its chloride? (d) Predict the solubility of its chloride?
17.a. Which among the following elements whose atomic numbers are given below belong to the same period? Give the reason. 17, 10, 20, 12, 19,15.
- Element X with atomic 12 and element Y with atomic number 17 reacts with hydrogen to form hydrides. Which of them is expected to have high melting points?
- Why the position of hydrogen is not justified in the Modern periodic table?
- Name the element with atomic number 12.
- Name a metal in making cans and member of group 14.
- The most electronegative element in the periodic table.
- The horizontal rows in the periodic table.
- On moving across the period, atomic size of the element increase or decreases.
- Who gave the classification on basis of musical notes?
- Name two elements belonging to group 1 which can be cut with the help of a knife. What name is given to the elements belonging to group 2 of the periodic table and why?
Write the Name of the Elements in Q.25 to 27.
- A lustrous non metal having 7 valence electrons.
- Highly reactive metal gives violet colour to flame.
- A gas used in coloured advertising lights having 2 valence electrons.