Aquantity of 8.10 × 102 ml of 0.600 m hno3 is mixed with 8.10 × 102 ml of 0.300 m ba(oh)2 in a constant-pressure calorimeter of negligible heat capacity. the initial temperature of both solutions is the same at 18.46°c. the heat of neutralization when 1.00 mol of hno3 reacts with 0.500 mol ba(oh)2 is −56.2 kj/mol. assume that the densities and specific heats of the solution are the same as for water (1.00 g/ml and 4.184 j/g · °c, respectively). what is the final temperature of the solution?

22.48°C is the final temperature of the solution.

Explanation:

Heat of neutralization of reaction , when 1 mol of nitric acid reacts= ΔH= -56.2 kJ/mol= -56200 J/mol

Moles of nitric acid = n

Volume of nitric acid solution =

Molarity of the nitric acid = 0.600 M

Moles of barium hydroxide = n'

Volume of barium hydroxide solution =

Molarity of the barium hydroxide= 0.300 M

According to reaction, 2 mol of nitric acid reacts with 1 mol of barium hydroxide .Then 0.486 mol of nitric acid will react with :

barium hydroxide.

Heat release when 0.486 mol of nitric acid reacted = Q

= ΔH × 0.486 = -56200 J/mol × 0.486 mol=-27,313.2 J

Heat absorbed by the mixture after reaction = Q' = -Q = 27,313.2 J

Volume of the nitric solution = 0.81 L = 810 mL

Volume of the ferric nitrate solution = 0.81 L = 810 mL

Total volume of the solution = 810 mL + 810 mL = 1620 mL

Mass of the final solution = m

Density of water = density of the final solution = d = 1 g/mL

Initial temperature of the both solution were same =

Final temperature of the both solution will also be same after mixing=

Heat capacity of the mixture = c = 4.184 J/g°C

Change in temperature of the mixture = ΔT =

22.48°C is the final temperature of the solution.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !