The solution for this problem is:
The information given lacks but nevertheless the answer is:
So, the total heat free by dissolving the solute was 1386 + 32 = 1417 J
Then, dissolving of the solute will have released -1417 J. So, per gram of Al2
(SO4)3 dissolved:
-1417 J / 25 g = -56.7 J/g
Translating that to a per mole: -56.7 J/g X 342 g/mol = -1.94X10^4 J/mol = -19
kJ/mol = this would be Delta Hsoln
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Answer:
54 g
Explanation:
Given data:
Mass of carbon = 18 g
Mass of CO₂ = 72 g
Mass of oxygen needed = ?
Solution:
Chemical reaction:
C + O₂ → CO₂
according to law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In a similar way,
C + O₂ → CO₂
18 g + X = 72
X = 72 -18
X = 54 g
Thus, 54 g of O₂ are required.
Answer:
75000 Hz
Explanation:
f = V / λ (f= frequency, v=velocity of wave, lambda= wavelength)
alternatively, f = c / λ (f= frequency, c= speed of light- 3.00x10^8 m/s, lambda= wavelength)
f= [3.00x10^8 m/s]/[4000 m]
=75000 Hz
