Answer:
ΔH = +26.08 kJ/mol
Explanation:
The change in enthalpy (ΔH) is given in J/mol, and can be calculated for dissolution by the equation:
ΔH = m(water)*Cp*ΔT/n(solute)
The mass of water is the density multiplied by the volume
m = 1g/mL * 25.0mL = 25.0 g
The number of the moles is the mass divided by the molar mass. Knowing the molar masses of the elements:
N = 14 g/mol x 2 = 28
H = 1 g/mol x 4 = 4
O = 16 g/mol x 3 = 48
NH₄NO₃ = 80 g/mol
n = 1.25/80 = 0.015625 mol
So,
ΔH = 25*4.18*(25.8 - 21.9)/0.015625
ΔH = 26,083.2 J/mol
ΔH = +26.08 kJ/mol
Patent - Not sure if this is much of a Chem question dou.
(4.5 x 10^24 molecules) x (60.013 g / 6.022 x 10^23) = 448 grams or 4.484 x 10^2 grams = Answer
Answer:
You can tell types of matter apart based on their properties. Physical properties of matter can be observed or measured without changing the identity of the substance.... Characteristic physical properties are properties that are always the same for a substance - so they can be used to identify a substance.
Explanation:
