For the reaction: 2 A + B2 --->> 2 AB Triangle H = -30.0 kJ a. The reaction is endothermic.

b. Heat is released to the surroundings.

c. The standard enthalpy of formation for AB is 30.0 kJ.

d. The bond energy for each A-B bond is 30.0 kJ.

Compound with sulfer  is bright red 

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf   

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