An unknown substance has a mass 26.3 g. The temperature of the substance increases by 11.9 degrees C when 73.5 J of heat is added to the substance. What is the most likely identity of substance?

Question

An unknown substance has a mass 26.3 g.  The temperature of the substance increases by 11.9 degrees C when 73.5 J of heat is added to the substance.  What is the most likely identity of substance?

Noah Aldrich · Accepted Answer

Silver.

The idea here is that you need to use the information provided by the problem to calculate the specific heat of the substance. Once you know this value, you can compare it to listed specific heat values of known substances and see if you can get a match. So, the specific heat of a substance is a measure of the amount of heat needed to increase the temperature of #"1 g"# of that substance by #1^@"C"#. You can calculate the specific heat of a substance by using the equation #color(blue)(ul(color(black)(q = m * c * DeltaT)))# Here Rearrange this equation to solve for the specific heat of the substance #q = m * c * DeltaT implies c = q/(m * DeltaT)# Plug in your values to find #c = "73.5 J"/("26.3 g" * 11.9^@"C") = "0.235 J g"^(-1)""^@"C"^(-1)# This specific heat is actually very close to the value listed for silver #c_"silver" = "0.233 J g"^(-1)""^@"C"^(-1)# https://tutor.hix.ai so you can conclude that your unknown substance could very well be silver.

Serenity Allen · Answer

undefined The most likely identity of the substance is aluminum (Al).