Answer:
88,7 mL of solution
Explanation:
Molarity (Represented as M) is an unit of chemical concentration that is defined as the ratio between moles of solute per liters of solution, that is:
Molarity = moles of solute / Liters of solution
If molarity of KCN solution is 0,0820M and moles of KCN are 7,27x10⁻³ moles:
0,0820M = 7,27x10⁻³ moles / Liters of solution
Liters of solution = 0,0887L = <em>88,7 mL of solution</em>
I hope it helps!
<span>The water cycle has no starting point. But, we'll begin in the oceans, since that is where most of Earth's water exists</span>
Answer:
ΔH rxn = -1010 kJ/molC₂H₂
Explanation:
To obtain the enthalpy change for a reaction from bond energies what we do is to make an inventory of the bonds broken and formed for the balanced chemical reaction:
C₂H₂ + 5/2O₂ ⇒ 2CO₂ + H₂O
Bond Broken Bonds Formed
2 C-H + 1 C≡C + 5/2 O=O 4C=O + 2 H-O
Enthalpy bonds broken:
2 mol (456 kJ/mol)+ 1 mol (962 kJ/mol) + 5/2 mol (499 kJ/mol) = 3121.5 kJ
Enthalpy bond formed:
4 mol (802 kJ/mol) + 2 mol (462 kJ/mol) = 4132.0 kJ
ΔH rxn = H broken - H formed = 3121.5 kJ - 4132.0 kJ = - 1010 kJ (per mol C₂H₂ )
Number of moles ( substance x ):
1 mole --------- 58.45 g/mol
? mole --------- 326.0 g
326.0 x 1 / 58.45 => 5.577 moles
heat of fusion:
hf = Cal / moles
hf = 4325.8 Cal / 5.577 moles
hf = 775.65 cal/mol
hope this helps!