Answer:
ΔH° = -186.2 kJ
Explanation:
Hello,
This case in which the Hess method is applied to compute the required chemical reaction. Thus, we should arrange the given first two reactions as:
(1) it is changed as:
SnCl2(s) --> Sn(s) + Cl2(g)...... ΔH° = 325.1 kJ
That is why the enthalpy of reaction sign is inverted.
(2) remains the same:
Sn(s) + 2Cl2(g) --> SnCl4(l)......ΔH° = -511.3 kJ
Therefore, by adding them, we obtain the requested chemical reaction:
(3) SnCl2(s) + Cl2(g) --> SnCl4(l)
For which the enthalpy change is:
ΔH° = 325.1 kJ - 511.3 kJ
ΔH° = -186.2 kJ
Best regards.
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Answer:
Step 1: The Unbalanced Chemical Equation. The unbalanced chemical equation is given to you. ...
Step 2: Make a List. ...
Step 3: Identifying the Atoms in Each Element. ...
Step 4: Multiplying the Number of Atoms. ...
Step 5: Placing Coefficients in Front of Molecules. ...
Step 6: Check Equation. ...
Step 7: Balanced Chemical Equation.
Explanation:
2H₂₍g₎ + O₂ ₍g₎→ 2H₂O
138 mol H₂ × (2 mol H₂O ÷ 2 mol H₂)= 138 mol H₂O
64 mol O₂ × (2 mol H₂O ÷ 1 mol O₂)= 128 mol H₂O
128 mol H₂O
Explanation:
As it is known that molarity is the number of moles present in a liter of solution.
Mathematically, Molarity = 
As it is given that molarity is 0.10 M and volume is 10.0 ml. As 1 ml equals 0.001 L. Therefore, 10.0 ml will also be equal to 0.01 L.
Hence, putting these values into the above formula as follows.
Molarity =
0.10 M = 
no. of moles = 0.001 mol
As molar mass of KCN is equal to 65.12 g/mol. Therefore, calculate the mass of KCN as follows.
No. of moles = 
0.001 mol = 
mass = 0.06152 g
Thus, we can conclude that 0.06152 grams of KCN are in 10.0 ml of a 0.10 M solution.
