Chemistry
Electronic configuration is the distribution of electrons in the various energy shells of an atom. It is based on the Bohr-Bury scheme, which states that :
- The maximum number of electrons that can be accommodated in a shell is given by 2n2, where n is the shell number.
- The outermost shell cannot have more than 8 electrons.
- A new shell starts filling once the inner shell acquires eight electrons.
Based on the information given above, answer the following questions:
(a) Write the electronic configuration of an atom X with atomic number 19.
(b) Draw the orbital diagram of the ion formed by atom X.
(c) Draw the complete orbital diagrams of the atoms 35Cl and 37Cl.
(d) Which fundamental particle differs in the atoms mentioned in part (c)?
(e) State the general term used for the atoms given in part (c).
Related Questions
Assertion (A): The valency of an element is its combining capacity with an atom of another element.
Reason (R): Elements take part in chemical combination to acquire the electronic configuration of the nearest noble gas.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Some main features of the structure of an atom are :
(i) Atoms of all the elements (except hydrogen) are made up of three fundamental (sub-atomic) particles: electrons, protons and neutrons. (Hydrogen atom lacks neutrons).
(ii) The nucleus is located at the centre of the atom. It contains protons and neutrons, which account for the total mass of that atom.
(iii) The nucleus is positively charged due to the presence of protons in it.
(iv) The electrons are outside the nucleus and have negligible mass.
Answer the following:
(a) What is the charge of nucleus ? Give reason.
(b) Atom is positively charged, negatively charged or neutral ? Why ?
(c) Why do only protons and neutrons account for the total mass of an atom ?
(d) What do you mean by orbits ?
(e) Draw a figure showing the 3 fundamental particles in an atom.
An element Y has electronic configuration 2, 8, 2.
Another element X has electronic configuration (2, 8, 7). The number of valence electrons of Y is 2 and that of X is 7. An atom of Y acquires a stable configuration of 8 electrons by losing two electrons from its outermost shell (one each to each atom of X) and thus becomes a positive ion, Y2+.However an atom of X, which contains 7 electrons in its outermost shell, can accept only 1 of the 2 electrons donated by an atom of Y. Therefore, for each Y atom forming a Y2+ ion, there must be two X atoms to form two X- ions.
(a) Which type of bond does this compound form ?
(b) In the formation of the compound …………… (transfer/sharing) of electrons takes place.
(c) Name two other compounds that form this type of a bond.
(d) Draw the orbital diagram for the formation of this compound.
(e) This type of bond is formed between …………… (metals and metals/metals and non metals/non metals and non metals).
(f) Can the above compound conduct electricity ?
An element X has one electron in N shell, Y has two electrons in M shell, Z has six electrons in M shell and P has four electrons in L shell.
(a) Write the electronic configuration of X, Y, Z and P.
(b) Which of these element are metals ?
(c) Which two elements can combine to form :
- an ionic bond
- a covalent bond
(d) Write the formula of the ionic and covalent compound that will be formed above in (c).
(e) Which of the above two compounds will have a high melting point ? Why ?