Students in mr. klein’s chemistry class are conducting an experiment to calculate the specific heat of a copper sample. mr. klein requires each lab team to repeat the experiment until their percent error is 2% or less. percent error is calculated using observed values (those students calculate from their lab results) and the true value (the accepted value based on reference). the formula for percent error is: (observed – true) x 100 true if the accepted value for the specific heat of copper is 0.385 j/g°c, which of the following lab teams have an unresolved problem on their hands

a.

team 1: calculates 0.392 j/gºc
b.

team 2: calculates 0.395 j/gºc
c.

both teams
d.

neither team

If a plot weight (in g) vs. volume (in ml) for a metal gave the equation y= 13.41x and r^2=0.9981 what is the density of the metal?

Based on the equation and the information in the table, what is the enthalpy of the reaction?

Straightforward questions answered in the powerpoint slidesreaction: heating the starting materials under refluxwhat does it mean to heat under reflux? why do we choose water as the reflux solvent? what are boiling chips used for? why do we put a condenser on top of the reaction? why do we add heat and let the reaction stir for 30 minutes? why do we add sulfuric acid to the reaction after it cools as opposed to when it’s still hot? separation: filtration of precipitatewhy don’t we do an aqueous and organic extraction in the separatory funnel? why do you rinse the salicylic acid on the filter with ice cold water? purification: recrystallization of salicylic acid (no hot filtration needed)what is the difference in the amount of room temperature water vs. boiling water needed to dissolve the salicylic acid (assume a 1.2 gram yield of salicylic acid)? remember, in the lab if you need x ml of boiling water to dissolve a solid, then you should add a little more (definitely no more than 1.5 times the theoretical amount) to ensure it doesn’t recrystallize prematurely.analysis: melting point of salicylic acidwhat can you conclude if the melting point of the salicylic acid you just synthesized is 152-155oc and the 1: 1 mix of your product and “synthetic” salicylic acid is 151-154oc?