... in neutralization reactions, for example:
NaOH + HCl = NaCl + H₂O
2KOH + H₂SO₄ = K₂SO₄ + 2H₂O
<span>MicroR Meter, with Sodium Iodide Detector
<span>Geiger Counter, with Geiger-Mueller (GM) Tube or Probe
<span>Portable Multichannel Analyzer</span>
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The atom that would gain two electrons to fill its valence energy level is S(sulfur)
This is because s (sulfur) is in atomic number 16 with 2.8.6 of [Ne] 3s^2 2p^4 electronic configuration. This implies that sulfur has 6 valence electron and therefore it require two electron to fill its valence energy level and obtain 18 rule electrons.
In an exothermic reaction, heat is transferred to the surrounding.
Hope this helps, have a great day ahead!
