Answer:
a) 0.210 j
/k
b) 0.032 j/k
Explanation:
Find the attachment for solution
It matches the universal pH indicator and is indicating the proper pH
Answer is: empirical formula of the product is Br₂O₅.
Chemical reaction: x/2Br₂ + y/3O₃ → BrₓOy.
m(Br₂) = 1,250 g.
m(BrₓOy) = 1,876 g.
n(Br₂) = m(Br₂) ÷ M(Br₂).
n(Br₂) = 1,25 g ÷ 159,81 g/mol.
n(Br₂) = 0,0078 mol.
n(Br) = 2 · 0,0078 mol = 0,0156 mol.
m(O₃) = 1,876 g - 1,25 g = 0,626 g.
n(O₃) = 0,626 g ÷ 48 g/mol = 0,013 mol.
n(O) = 0,039 · 3 = 0,039 mol
n(Br) : n(O) = 0,0156 mol : 0,039 mol.
n(Br) : n(O) = 1 : 2,5.
The Beer-Lambert law states that A = E*c*l where A is absorbance, E is the molar absorbance coeffecient, c is concentration and l is path length. Therefore the absorbance is directly proportional to concentration, and by increasing the concentration by a factor of 3, absorbance will increase by a factor of 3 giving A = 1.584
First step is to balance the reaction equation. Hence we get
P4 + 5 O2 => 2 P2O5
Second, we calculate the amounts we start with
P4: 112 g = 112 g/ 124 g/mol – 0.903 mol
O2: 112 g = 112 g / 32 g/mol = 3.5 mol
Lastly, we calculate the amount of P2O5 produced.
2.5 mol of O2 will react with 0.7 mol of P2O5 to produce 1.4
mol of P2O5.
This is 1.4 * (31*2 + 16*5) = 198.8 g
