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
D because 0 is always ignorant in significant figures. hope that helps:)
Answer:
It will cost $35.5602
Explanation:
$2.459 /6.5 (mpg) = 0.3783 (cents per mile)
$0.3783 (cost per mile) * 94 (total miles) = $35.5602 total
Gravitational force will increase with greater mass
