4. A sealed glass tube contains 2.25 g of copper and 3.32 g of sul- fur. The mass of the tube and its contents is 18.48 g. Upon
heating, a reaction forms copper(II) sulfide (Cus). All of the
copper reacts, but only 1.14 g of sulfur reacts. Predict what the
mass of the tube and its contents will be after the reaction is
completed. Explain your reasoning.​

answer; /// i do believe that the correct answer is (a) boiling

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.