Answer:
sending heat waves and vibrations
Answer:
0.00335 moles
Explanation:
From the question, Using
PV = nRT................... Equation 1
Where P = pressure, V = Volume, n = number of moles of argon gas, R = Molar gas constant, T = Temperature.
make n the subject of the equation
n = PV/RT............... Equation 2
Given: P = 1 atm (standard pressure), T = 273 K (standard temperature), V = 75 mL = 0.075 dm³
Constant: R = 0.082 atm·dm³/K·mol
Substitute into equation 2
n = (1×0.075)/(273×0.082)
n = 0.075/22.386
n = 0.00335 moles
Answer: The enthalpy of the given reaction is 1234.8kJ/mol.
Explanation: Enthalpy change of the reaction is the amount of heat released or absorbed in a given chemical reaction.
Mathematically,
For the given reaction:
![\Delta H_{rxn}=\Delta H_f_{(C_2H_5OH)}+3\Delta H_f_{(O_2)}-[2\Delta H_f_{(CO_2)}+3\Delta H_f_{(H_2O)}]](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5CDelta%20H_f_%7B%28C_2H_5OH%29%7D%2B3%5CDelta%20H_f_%7B%28O_2%29%7D-%5B2%5CDelta%20H_f_%7B%28CO_2%29%7D%2B3%5CDelta%20H_f_%7B%28H_2O%29%7D%5D)
Putting values in above equation, we get:
![\Delta H_{rxn}=[-277.6+3(0)]-[2(-393.5)+3(-241.8)]kJ/mol](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5B-277.6%2B3%280%29%5D-%5B2%28-393.5%29%2B3%28-241.8%29%5DkJ%2Fmol)
Answer:-
KOH determines how much Mg(OH)2 is made.
2 mol of Mg(OH)2 formed
Explanation:-
The balanced equation is
MgCl2 + 2KOH --> Mg(OH)2+ 2KCI,
From seeing the coefficients we notice
2 mol of KOH reacts with 1 mol of MgCl2
4 mol of KOH reacts with 1 x 4 / 2 = 2 mol of MgCl2
3 moles of MgCl2 was added but only 2 mol react.
So we see there is excess MgCl2 .
Hence KOH is the limiting reactant.
So KOH determines how much Mg(OH)2 is made.
We see from the balanced chemical equation,
2 mol of KOH gives 1 mol of Mg(OH)2.
4 mol of KOH will give 1 x 4 /2 = 2 mol of Mg(OH)2.
