NH4Cl(s) → NH3(g) + HCl(g) ∆H0=176 kJ/mol ∆S0=0.285 kJ/(mol K) What can be deduced from to this reaction?

At room temperature, the reaction is not spontaneous. However, at high temperatures, like 800 °C, the free energy value turns negative and this reaction becomes spontaneous.

At room temperature, the reaction is spontaneous. If the temperature is increased, the free energy value turns negative and the reaction stays spontaneous.

At room temperature, the reaction is spontaneous. However, at high temperatures, like 800 °C, the free energy value turns negative and this reaction becomes nonspontaneous.

At room temperature the reaction is not spontaneous. However, at lower temperatures, like –40 °C, the free energy value turns negative and this reaction becomes spontaneous.

the electrical  conductivity  of asolution  of an electrolyte is measured by determining the resistance of thesolution  between two flat or cylindrical electrodes separated by a fixed distance.

what is the average time it took the car to travel 0.25 meters?

⇒ 2.23 seconds

what is the average time it took the car to travel 0.50 meters?

⇒ 3.13 seconds

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2