Answer : The correct option is C.
Explanation :
Enthalpy of reaction : It is defined as the changes in heat energy takes place when reactants go to products. It is denotes as .
= Energy of product - Energy of reactant
is positive when heat is absorbed and the reaction is endothermic.
is negative when heat is released and the reaction is exothermic.
In the given potential energy diagram, the energy of product at higher level and energy of reactant at lower level. The for this reaction will be positive.
So, the enthalpy of reaction is defined as the difference of the energy of the reactants and the energy of the products.
Answer:
2.138 x 10^26 atoms Na
Explanation:
atoms Na = 355 mol Na x (6.022 x 10^23 atoms Na/1 mol Na) = 2137.81 x 10^23 atoms Na = 2.138 x 10^26 atoms Na
Answer:
mass (m) is measured in kilograms (kg) specific heat capacity (c) is measured in joules per kilogram per degree Celsius (J/kg°C) temperature change (∆θ) is measured in degrees Celsius (°C)
Explanation:
Answer:
-1960 kJ.
Step-by-step explanation:
C₄H₄O₄(s) + 3O₂(g) ⟶ 2H₂O((ℓ)) + 4CO₂(g) + Energy
There are three energy flows in this reaction.
From combustion + warm water + warm calorimeter = 0
q₁ + q₂ + q₃ = 0
nΔH + mCwΔT + CcalΔT = 0
<em>Data:
</em>
Mass of fumaric acid = 1.1070 g
Mass of water = 1.093 × 10³ g
Cw = 4.184 J·°C⁻¹g⁻¹
T₁ = 21.10 °C
T₂ = 24.52 °C
Ccal = 891.1 J·°C⁻¹
Calculations:
(a) <em>q₁
</em>
n = 1.1070 g × (1 mol/116.07 g)
n = 0.009 537 mol
q₁ = 0.009 537ΔH J
(b) <em>q₂
</em>
ΔT = 24.52 – 21.10
ΔT = 3.42°C
q₂ = 1093 × 4.184 × 3.42
q₂ = 15 640 J
(c) <em>q₃
</em>
q₃ = 891.1 × 3.42
q₃ =3048 J
(d) <em>ΔH</em>
0.009 537ΔH + 15 640 + 3048 = 0
0.009 537ΔH + 18 688 = 0
0.009 537ΔH = -18 688
ΔH = -18 688/0.009 537
ΔH = -1 959 413 J/mol
ΔH = -1960 kJ/mol
This is quite different from the actual value of -1334.70 kJ·mol⁻¹
Answer:
Bohr thought that electrons orbited the nucleus in quantised orbits. ... In Rutherford's model most of the atom's mass is concentrated into the centre (what we now call the nucleus) and electrons surround the positive mass in something like a cloud. Bohr's most significant contribution was the quantisation of the model.
Explanation: