Which of the following is heat absorbed by a substance melting from a solid to a liquid

A substance absorbs heat during two major changes in its state which are melting and boiling

When a solid substance absorbs enough heat, it starts to liquefy due to the intense energy of the constituent atoms and molecules. Example melting of ice.

When a liquid absorbs heat, it starts to vaporize and escape into the atmosphere.

Explanation:

During the change of solid to liquid called melting or fusion and during change of liquid to gas called as vaporization or boiling the heat is absorbed to overcome the force of attraction between molecules of that specific component called as hidden heat that is LATENT heat may be latent heat of fusion or vaporization

1.consider the following balanced equation and answer parts a through. show calculations for each part.  

3 ag(s) + 4 hno3(aq) → 3 agno3(aq) + no(g) + 2 h2o(l)  

a. calculate the number of moles of agno3 produced by the reaction of 3 moles of ag with excess hno3. if the number to the left of the compound represents the number of moles of the compound which are present, then 3 moles of ag react with 4 moles hno3 to produce 3 moles agno3 (aq).

so the answer to a would be 3 moles.

b. calculate the number of moles of agno3 produced by the reaction of 108 grams of ag with excess hno3.  

i'm not sure how to plug in the grams of silver into an equation using moles to find how many moles are produced.

c. calculate the number of grams of agno3 produced by the reaction of 108 grams of ag with excess hno3  

d. calculate the number of moles of no produced as a byproduct of the reaction of 108 grams of ag with excess hno3.  

e. calculate the number of grams of no produced as a byproduct starting with 108 grams of ag and excess hno3.  

explanation:

increased stability in the completion of fluorine's outer shell.