Answer:
The heat of the solution of salt is 1.66.11 J/g.
Explanation:
Mass of the water = m = 46.52 g
Initial temperature of the water =
Final temperature of the water =
The specific heat of water, c = 4.180 J/gºC
Heat associated with water on dissolving salt: q
Negative sign means that heat was lost by water on an addition of a salt.
Heat released on dissolving of salt = -Q = 748.65 J
Mass of salt added = 4.5069 g
Heat of the solution of salt :
=
The heat of the solution of salt is 1.66.11 J/g.
The answer is 172.39950000000002
Answer:
The correct answer is 0.36 mol
Explanation:
First we have to calculate the molecular weight (Mw) of H₃BO₃ from the molar masses of the elements:
Mw(H₃BO₃)= 3 x Molar mass H + Molar mass B + (3 x Molar mass O)
= 3 x 1 g/mol + 10.8 g/mol + (3 x 16 g/mol)
= 61.8 g/mol
The molecular weight indicates that there are 61.6 grams per mol of substance. The scientist has 22.5 g, thus we can calculate the number of moles of H₃BO₃ by dividing the mass into the molecular weight as follows:
Number of moles of H₃BO₃ = mass/Mw= (22.5 g)/(61.8 g/mol) = 0.36 mol
There are 0.36 mol of H₃BO₃ in 750.0 mL of solution.