In discharge tube gases are good conductors of electricity at very low pressure and high veltage due to
1) Presence of atoms
3) presence of electrons only
2) Presence of molecules
4) Presence of ions and electrons
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100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)