Which elements are you talking about?
A. N₂ (g) + 3 H₂ (g) --> 2 NH₃ (g)
B. The value for standard enthalpy of formation is empirical given that the reactants involved were pure elements. So, you can search this on the internet or in any textbook. The Hf for NH₃ is -46.0 kJ/mol.
C. C (s) + O₂ (g) --> CO₂ (g)
D. The Hf for CO₂ is <span>-393.5 kJ/mol
E. 4 Fe (s) + 3 O</span>₂ (g) --> 2 Fe₂O₃ (s)
F. The Hf for solid Fe₂O₃ is -826.0 kJ/mol.
G. C (s) + 2 H₂ (g) --> CH₄ (g)
H. The Hf for methane gas is -74.9 kJ/mol.
Answer:
0.116%
Explanation:
efficiency of sterling engine = 1 - ( 55 + 273 )k / ( 95 + 273 ) k
= 1 - ( 328 / 368 ) = 0.10869
<u>Determine how efficient the transfer of energy via flame is </u>
apply this relation ; energy of steady state / energy output ---- ( 1 )
where; <em><u>energy output</u></em> = efficiency of sterling engine * energy
= 0.10869 * 50 = 5.4345 J/sec
<em><u>energy of steady state</u></em> = 1/2 * I * w^2 ------ ( 2 )
I = moment of inertia of engine = 2 * 10^-5 kgm^2
back to equation 2 :
energy of steady state = 1/2 * ( 2 * 10^-5 ) * ( 240 * 2π / 60 )^2
= 630.88 * 10^-5 J /sec
Input values into equation 1
= [ (630.88 * 10^-5 ) / 5.4345 ] * 100
= 0.116%
Answer:
Q1: c. 7.2 g.
Q2: a. 0.42 M.
Explanation:
Hello there!
In this case, according to the definition of molarity as moles of solute divided by volume of solution in liters, we can proceed as follows:
Q1: Here, given the molarity and volume we can calculate the moles of the sugar as follows:
Next, since its molar mass is about 180 g/mol, the mass turns out:
Therefore, the answer is c. 7.2 g.
Q2: Here, recalling the definition of molarity, we can just plug in the 0.629 moles and 1.500 L to obtain:
Therefore, the answer is a. 0.42 M.
Best regards!