The heat that is required to raise the temperature of an object is calculated through the equation,
heat = mass x specific heat x (T2 - T1)
Specific heat is therefore calculated through the equation below,
specific heat = heat / (mass x (T2 - T1))
Substituting,
specific heat = 645 J / ((28.4 g)(15.5 - - 11.6))
The value of specific heat from above equation is 0.838 J/g°C.
Answer: 20 gallons of 16% and 8 gallons of 23% solution is usedfor 28 gallons of the 18 % solution.
Explanation:
According to the dilution law,
where,
= concentration of ist disinfectant solution = 16 %
= volume of pure acid solution = x gallons
= concentration of another disinfectant solution= 23%
= volume of another acid solution= (28-x) gallons
= concentration of resulting disinfectant solution = 18 %
= volume of resulting acid solution = 28 gallons

(28-x) = (28-20) = 8 gallons
Thus 20 gallons of 16% and 8 gallons of 23% solution is usedfor 28 gallons of the 18 % solution.
ALL organic molecules have carbon.
Hope this helps :)