An instant cold pack purchased in a pharmacy contains a packet of solid ammonium nitrate surrounded by a pouch of water. When the packet of NH4NO3 is broken, the solid dissolves in water and cooling of the mixture occurs because the solution process for NH4NO3 is endothermic. Explain, in terms of what happens to the molecules and ions, why this mixing occurs spontaneously. A. In solution, the ions NH4+ and NO3- are highly ordered throughout the solvent.
B. In the solid, the ions in NH4NO3 are highly ordered.
C. In solution, the ions NH4+ and NO3- are randomly distributed throughout the solvent.
D. The increase in randomness makes the process spontaneous.
E. The decrease in randomness makes the process spontaneous.

c

letra c certeza confia

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).