Answer:
equal to M
Explanation:
The mass of the fully melted mass and the initial solid will be the same. So, the mass of the melt is equal to M.
Mass is the amount of matter contained within a substance. Since only the phase changed and the amount of matter is still the same, the mass of the molten phase and the solid phase will remain the same.
We are correct to say that in the heating process no mass was destroyed or added in melting the solid.
A simple phase change that preserved the mass only occurred.
Answer and Explanation:
For the following balanced reaction:
PCl₅(g) ↔ PCl₃(g) + Cl₂(g)
We can see that all reactants and products are gases, so it is an homogeneous equilibrium. The expression for the equilibrium constant Kp can be written from the partial pressures (P) of reactants and products as follows:

Where PPCl₃ is the partial pressure of PCl₃ (reactant), PCl₂ is the partial pressure of Cl₂ (reactant) and PPCl₅ is the partial pressure of PCl₅ (product).
Answer: Metals form cations.
The alkali metals (the IA elements) lose a single electron to form a cation with a 1+ charge.
The alkaline earth metals (IIA elements) lose two electrons to form a 2+ cation.
Aluminum, a member of the IIIA family, loses three electrons to form a 3+ cation.
Therefore, metals in the s and p block of the periodic table have 1, 2 or 3 electrons in their outermost orbit (or valence shell). Now to gain a stable octet metals lose either 1, 2 or 3 electrons from the valence shell thus forming cation with +1, +2 or +3 charge.
Electric current is flow of electrons in a conductor. The force required to make current flow through a conductor is called voltage and potential is the other term of voltage.