Answer:
ΔHr = -86.73 kJ/mol
Explanation:
Using Hess's law, you can calculate ΔH of any reaction using ΔH°f of products and reactants involed in the reaction.
<em>Hess law: ∑nΔH°f products - ∑nΔH°f reactants = ΔHr</em>
<em>-Where n are moles of reaction-</em>
For the reaction:
Fe³⁺(aq) + 3 OH⁻(aq) → Fe(OH)₃(s)
Hess law is:
ΔHr = ΔH°f Fe(OH)₃ - ΔH°f Fe³⁺ - 3×ΔH°f OH⁻
Where:
ΔH°f Fe(OH)₃: −824.25 kJ/mol
ΔH°f Fe³⁺: −47.7 kJ/mol
ΔH°f OH⁻: −229.94 kJ/mol
Replacing:
ΔHr = −824.25 kJ/mol - (−47.7 kJ/mol) - (3×-229.94 kJ/mol)
<em>ΔHr = -86.73 kJ/mol</em>
Answer: 7.71 + 4.31 + 1.7 + 4.00141=
17.72141
7.71 x 4.31 x 1.7 x 4.00141= 226.04433255
Explanation:
(i) 7.71 + 4.31 + 1.7 + 4.00141
= 7.71000+4.31000+1.70000+ 4.00141 [make like decimals]
= 17.72141 [By adding the corresponding places ]
(ii) 7.71 x 4.31 x 1.7 x 4.00141 =( 7.71 x 4.31) x 1.7 x 4.00141
= 33.2301 x 1.7 x 4.00141
= (33.2301 x 1.7) x 4.00141
= 56.49117 x 4.00141
= ( 56.49117 x 4.00141 )
= 226.04433255
Hence, 7.71 + 4.31 + 1.7 + 4.00141=
17.72141
7.71 x 4.31 x 1.7 x 4.00141= 226.04433255
<span>Answer:
Q = 500.0 x 4.18 x 8.63 = 18037 J => 18.037 kJ
moles anthracene = 0.455 g/ 178.234 g/mol=0.00255
0.00255 moles give 18.037 kJ
0.00255 : 18.037 = 1 mole : x
x = 7073 kJ/mol
enthalpy = - 70.73 kJ/mol</span>
The product when an unsaturated hydrocarbon undergoes complete addition would be a saturated molecule. These saturated hydrocarbons becomes Alkanes where these molecules are only single-bonded in contrary to unsaturated hydrocarbons which have multiple bonds between atoms.
Answer:
1.Handpicking,winnowing and sieving 2. distillation 3.distillation 5. winnowing 6.magnet
