(i) Calculate the total number of electrons present in 1 mole of methane .
(ii) Find (a) the total number and (b) the total mass of neutrons in 7 mg of `.^(14) C`. (Assume that mass of a neutron ` = 1 . 6 75 xx 10 ^(-27) g)`
(iii) Find (a) the total number of protons and (b) the total mass of protons in ` 32 mg` of ` NH_3` at ` STP`. ( mass of proton ` = 1 . 6 72 xx 10^(-27) g)`
Will the answer change if the temperature and pressure are changed ?

Explanation

Let's solve the question step by step.

### Part (i): Calculate the total number of electrons present in 1 mole of methane (CH₄).

1. **Determine the number of electrons in one molecule of methane:**
- Methane (CH₄) consists of:
- 1 Carbon (C) atom: Carbon has 6 electrons.
- 4 Hydrogen (H) atoms: Each Hydrogen has 1 electron, so 4 Hydrogen atoms have 4 electrons.
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