a) The reaction is exothermic since the overall enthalpy change is negative. this means that the system has lost energy to the environment, namely, the apparatus and due to drought.
b) We first calculate the number of moles in 3.55 grams of magnesium.
number of moles= mass/ atomic mass
=3.55/24
=0.1479 moles(to 4sf)
now, if 2 moles of magnesium give -1204kJ
How much energy is given by 0.1479 moles
= (0.1479×-1204kJ)
=-89.0358kJ (don't forget the negative sign)
c) two molesof MgO produces -1204kJ of energy
then -234kJ will be produced by
=(-234kJ×2moles)/1204kJ
=0.3887moles
one mole of MgO weighs 24+16=40
therefore the mass produced is 0.3887moles×40=15.548grams
(d) we first find the number of moles of MgO in 40.3 grams
number of moles=mass/RFM
=40.3g/40= 1.0075moles
if 2 moles of MgO give 1204 kJ then decomposing 1.0075 moles requires
(1.0075 moles×1204kJ)/2=606.515kJ
Answer:
16.5 g
Explanation:
The van't Hoff factor is a relation between the ideal value of a solution's colligative properties and the observed colligative properties.
Check the attached files for detailed solution
The balanced equation for the above reaction is as follows;
2C₁₀H₂₂ + 31O₂ ---> 20CO₂ + 22H₂O
stoichiometry of C₁₀H₂₂ to CO₂ is 2:20
this means that for every 2 mol of C₁₀H₂₂ that reacts - 20 mol of CO₂ is formed
therefore when 5.0 mol of C₁₀H₂₂ reacts - 20/2 x 5.0 = 50 mol of CO₂ is formed
50 mol of CO₂ is produced.
Below are the choices:
<span>A. Ni(CO)4(g) ⇌ Ni(s) + 4CO(g)
B. C(s) +2H2(g) ⇌ CH4(g)
C. CaCO3(s) ⇌ CaO(s) + CO2(g)
D. N2(g) + O2(g) ⇌ 2 NO(g)
</span>
The answer is A. Ni(CO)4(g) ⇌ Ni(s) + 4CO(g)
<span>The Kp/Kc ratio is equal to (RT)Δn. K is a constant and the temperature is held constant. So, the Kp/Kc ratio depends on Δn or the difference of moles of gaseous product and reactant. The reaction with the greatest Kp/Kc ratio is Ni(CO)4(g) ⇌ Ni(s) + 4CO(g) with a Δn of 3.</span>
