33.6 moles are needed to completely react with 84.0 moles of O2
Answer:
1.991 kJ
Explanation:
Calculate the amount of heat ( J )
CH4 ;
coefficients are : a = 19.89 , b = 5.02 * 10^-2 , c = 1.269 * 10^-5 , d = -11.01 * 10^-9
attached below is the detailed solution
Answer:
76.5g KCl/74.55 grams per mole Kcl = x
molality= x/.085 kg H2O
Explanation:
well remember molality is moles of solute/kilograms of solvent. So it's the moles of KCl over 85 g of h20 converted into kg. if this makes sense.
Answer:
(A) endothermic
(A) Yes, absorbed
Explanation:
Let's consider the following thermochemical equation.
2 Fe₂O₃(s) ⇒ 4 FeO(s) + O₂(g) ΔH = 560 kJ
Since ΔH > 0, the reaction is endothermic.
We can establish the following relations:
- 560 kJ are absorbed when 2 moles of Fe₂O₃ react.
- The molar mass of Fe₂O₃ is 160 g/mol.
Suppose 66.6 g of Fe₂O₃ react. The heat absorbed is:
Answer: The mass of lead deposited on the cathode of the battery is 1.523 g.
Explanation:
Given: Current = 62.0 A
Time = 23.0 sec
Formula used to calculate charge is as follows.
where,
Q = charge
I = current
t = time
Substitute the values into above formula as follows.
It is known that 1 mole of a substance tends to deposit a charge of 96500 C. Therefore, number of moles obtained by 1426 C of charge is as follows.
The oxidation state of Pb in is 2. So, moles deposited by Pb is as follows.
It is known that molar mass of lead (Pb) is 207.2 g/mol. Now, mass of lead is calculated as follows.
Thus, we can conclude that the mass of lead deposited on the cathode of the battery is 1.523 g.