9th Class Science Structure of the Atom Question Bank Atomic Structure HOTS Subjective Problems

  • question_answer
    The electronic configuration of a tripositively charged ion\[({{X}^{+3}})\]is 2, 8. Then (a) (i) Identify the element. (ii) Find the number of neutrons in it. (b) Write the formula of the compound that it forms with chlorine and oxygen respectively. (c) Name the element whose dinegatively charged ion is isoelectronic with\[{{X}^{+3}}\] (d) What is valency of 'X'? (e) Find the number of electrons present in 'M' shell of its neutral atom.
    (a) (b) (c) (d) (e)
    \[i\] \[ii\]
    (a) Boron 10 \[BaC{{l}_{3}}\And {{B}_{2}}{{O}_{3}}\] Oxygen 2 2
    (b) Aluminium 14 \[AlC{{l}_{3}}\And A{{l}_{2}}{{O}_{3}}\] Oxygen 3 3
    (c) Aluminium 13 \[AlC{{l}_{3}}\And A{{l}_{2}}{{O}_{3}}\] Fluorine 2 3
    (d) Boron 9 \[BC{{l}_{3}}\And {{B}_{2}}{{O}_{3}}\] Nitrogen 3 2

    Answer:

    The electronic configuration of a tripositively charged ion\[({{X}^{+3}})\]is 2, 8. Therefore the number of electrons in its neutral atom \[10+3=13\] (a) Aluminium\[{{(}_{13}}A{{l}^{27}})\] \[\Rightarrow \]The number of neutrons in it \[=27-13=14\]. (b) \[AlC{{l}_{3}}\] and \[A{{l}_{2}}{{O}_{3}}\] (c) Oxygen (\[{{O}^{2}}\]has 10 electrons) (d) 3 (e) Electronic configuration of X is 2, 8, 3. Therefore, the number of ?M? electrons present in it is 3.


You need to login to perform this action.
You will be redirected in 3 sec spinner