Brass is a solution in which a solid is dissolved in a(n)
select one:
a. gas
b. liquid
c. water
d. solid

Brass is a solution in which a solid is dissolved in a solid.

Option D

Explanation:

Brass is an example of alloy, a proportionate mixture of two metals: zinc and copper. Alloys are solid-solid solutions where a metal is mixed with one or more other types of metals or non-metals to form a new material, better in mechanical and chemical properties than the original components.

Increased resistance to corrosive actions, increased strength and toughness, better electrical conductivity, wider temperature operability, etc. are some advantages of alloying. Brass is widely used in manufacturing appliance parts and tools including valves, gears and bearings.  

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.