Answer:
25.7 kJ/mol
Explanation:
There are two heats involved.
heat of solution of NH₄NO₃ + heat from water = 0
q₁ + q₂ = 0
n = moles of NH₄NO₃ = 8.00 g NH₄NO₃ × 1 mol NH₄NO₃/80.0 g NH₄NO₃
∴ n = 0.100 mol NH₄NO₃
q₁ = n * ΔHsoln = 0.100 mol * ΔHsoln
m = mass of solution = 1000.0 g + 8.00 g = 1008.0 g
q₂ = mcΔT = 58.0 g × 4.184 J°C⁻¹ g⁻¹ × ((20.39-21)°C) = -2570.19 J
q₁ + q₂ = 0.100 mol ×ΔHsoln – 2570.19 J = 0
ΔHsoln = +2570.19 J /0.100 mol = +25702 J/mol = +25.7 kJ/mol
4) is correct
This is because water is polar and it will mix with a polar solvent. A good rule for remembering the behavior of non-polar and polar compounds when it comes to being miscible is that "like dissolves like."
Objects float on water because it has surface tension.
Answer:
a. What is the wavelength?
The wavelength is 5 meters.
b. What is the frequency?
The frequency is 0.05Hz
c. What is the wave velocity?
The wave velocity is 0.25 meters per second
Explanation:
the wavelength is the distance between two troughs or two crests, which in this case is 5 meters.
the frequency=cycles/time. For this equation the equation would be 1/20, which is 0.05
the wave velocity=wavelength x frequency. Plug in the numbers, 5 x 0.05, and you will get 0.25.
Silicon-32's half-life is actually 710 years.