When 5.00 g of nh4no3 is dissolved in 100.0 g of water in a styrofoam cup, the t = - 3.82 ^°c. is the process of dissolving ammonium nitrate endo- or exothermic? what is the heat of this process in kj/mol?

The process is endothermic.

Heat is 26,9 kJ/mol

Explanation:

The dissolution of NH₄NO₃ in water is:

NH₄NO₃ → NH₄⁺ + NO₃⁻

As the change of temperature in the cup is ΔT = -3,82°C

The process is endothermic. Because the temperature is decreasing in the process. That means the process needs heat.

Assuming the  heat capacity of the solution is 4.18 J/Kg :

q = -C×m×ΔT

Where q is heat, C is heat capacity (4,18J/Kg), m is mass (105g) and ΔT is change in temperature (-3,82°C)

q = 1677 J ≈ 1,68kJ

The moles of NH₄NO₃ dissolved are:

5,00g × (1mol / 80,043g) = 0,0625 moles

That means heat of this process in kJ/ mol is:

1,68kJ / 0,0625moles = 26,9 kJ/mol

I hope it helps!

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

here is table 2-2:

country

percent of eligible voters that voted

rank

united states

44.9%

138

canada

60.1%

107

costa rica

84.6%

14

hungary

66.9%

82

japan

57.0%

118

egypt

27.7%

159

south africa

85.5%

10

ans is no, the data set cannot be plotted as a single circle graph