The atomic number of an element ‘X' is 19.
(a) Write its electronic configuration. (b) To which period of the Modern Periodic Table does it belong and what is its valency? (c) If 'X' burns in oxygen to form its oxide, what will be its nature - acidic, basic or neutral? (d) Write balanced chemical equation for the reaction when this oxide is dissolved in water.

Explanation

Let's solve the question step by step:

### Step 1: Determine the electronic configuration of element 'X' with atomic number 19.
- The atomic number of an element indicates the number of protons and, in a neutral atom, also the number of electrons.
- The electronic configuration is determined by filling the electron shells according to the Aufbau principle.
- For atomic number 19, the electron configuration can be filled as follows:
- 1st shell: 2 electrons
- 2nd shell: 8 electrons
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