Acertain chemical reaction releases of heat energy per mole of reactant consumed. suppose some moles of the reactant are put into a calorimeter (a device for measuring heat flow). it takes of heat energy to raise the temperature of this calorimeter by . now the reaction is run until all the reactant is gone, and the temperature of the calorimeter is found to rise by . how would you calculate the number of moles of reactant that were consumed?

To relate the quantity of a substance to the amount of heat transferred and heat capacity, temperature, number of moles is given by

q=ncpΔT

where

n is number of moles

cp is molar heat capacity

ΔT=Tfinal−Tinitial is the temperature difference

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.