<span>In the question ' which of the following most likely require intermolecular force', options A and C given are definitely not the correct answers. Among the items listed in the questions, the one that will most likely required an intermolecular force is a rock maintaing its solid shape. Thus, the correct option is B. Intermolecular forces are forces which maintain chemical interactions between molecules of a particular susbstance and other types of paticles that may be present in the substance. Rocks are made up of differet particles and their structures are held together by different types of intermolecular forces depending on the types of particles present in the rock. Intermolecular forces can only occur among molecules and other particles in a compound that is why the other two options are wrong. Intermolecular force can either be attractive or repulsive. Attraction occurs between molecules of opposite charges, that is, positive and negative charges while repulsion occurs between particles of like charges, for intstance, between positive and positive charges. The Intermolecular forces that exist in a compound maintaings the integrity of the structure of that compound. Intermolecular forces in compounds exist in different forms, we have electrovalent bonds, covalent bonds, hydrogen bond, vander waals forces, etc. The type of molecules that exist in a compound will determine the type of intermolecular forces that will exist among the molecules of that substance. Electrovalent bonds are the strongest type of intermolecular force and it normally exist between metals and non metals. Covalent bonds involved sharing of electrons among the participating elements while vander waals forces are the weakest form of intermolecular forces. Forces are often required to break intermolecular forces apart. Breaking the intermolecular forces apart will destroy the structure of the substance inlvolved.</span>
A chemical reaction does happen between sodium and water to form Sodium Hydroxide (NaOH) and Hydrogen Gas (H-2)
Grams of Phosphorus = 4.14 grams
Grams of white compound = 27.8 grams
Grams of Chlorine would be = 27.8 - 4.14 = 23.66 grams
Calculating moles which would be grams / molar mass
Molar mass of P = 30.97 grams / moles; Molar mass of Cl = 35.45 grams / moles
Moles of Phosphorus = 4.14 grams / 30.97 grams / moles = 0.1337 moles
Moles of Chlorine = 23.66 grams / 35.45 grams / moles = 0.6674 moles
Calculating the ratios by dividing with the small entity
P = 0.1337 moles / 0.1337 moles = 1
Cl = 0.6674 moles / 0.1337 moles = 5
So the empirical formula would be PCl5
Answer: 480 kJ of energy is released when 3.5 mol of 
reacts.
Explanation:
The balanced chemical reaction is:
Thus it is given that the reaction is exothermic (heat energy is released) as enthalpy change for the reaction is negative.
1 mole of on reacting gives = 137 kJ of energy
Thus 3.5 moles of on reacting gives = 
of energy
Thus 480 kJ of energy is released when 3.5 mol of reacts.
