A student dissolves 14.6 g of ammonium chloride (NHĻCI) in 200. g of water in a well-insulated open cup. She then observes the temperature of the water fall from 20.0 °C to 15.1 °C over the course of 8.3 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction:

NH4+ (aq) + Cl- (aq) > NH4CI(s)

calculate the amount of heat that was released or absorbed by the reaction in this case kJ per mole of NH4CI

q = 1.6 x 10⁴ kJ/ mol NH₄CI  

Explanation:

In this question we are given the change in temperature for the dissolution of 14.6 g NH₄Cl. We know from calorimetry that the change in temperature for a mass, m , of water is given by the expression:

q = m x c x Δt

where q is the heat absorbed or released upon dissolution, and c is the specific heat of water.

We have all that is needed to compute q for the dissolution of ammonium chloride, but please note we are being asked the q for the reverse reaction. Thus we would compute q reverse its sign and divide it by the number of moles in 14.6 g NH₄Cl to give the answer this question.

c for H₂O = 4.186 J/g ºC

ΔT = T final - Tinicial = 15.1 ºC - 20.0 ºC =  - 5.10 ºC

q = 200 g x 4.186 J/gºC x  - 5.1 ºC

  =  -4270 J = - 4.3 x 10³ kJ

Thus for the reverse reaction:

NH₄+ (aq) + Cl- (aq) > NH₄CI(s)

q = - ( - 4.3 x 10³ kJ ) = 4.3 x 10³ kJ

The molecular weight of  NH₄CI is 53.49 g /mol.

⇒ mol NH₄CI = 14.6 g /53.49 g/mol = 0.27 mol

and the heat absorbed per mol of NH₄CI  , endothermic reaction, is

q = 4.3 x 10³ kJ / 0.27 mol = 1.6 x 10⁴ kJ/ mol NH₄CI  

i dont know

explanation:

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.