In Part III, the phenolphthalein indicator is used to monitor the equilibrium shifts of the ammonia/ammonium ion system. The phe
nolphthalein equilibrium established with water is Hph(aq)(colorless) + H2O (l) H3O+ (aq) + ph-(aq)(pink or red). You compared the color of the solutions in three test tubes that initially contained 3 mL of 0.1 M ammonium hydroxide and a few drops of phenolphthalein indicator. In the first test tube, you added 1 M NH4Cl dropwise. What color change was observed and what did this color change indicate about the shift in the phenolphthalein equilibrium? a. The solution turned a more intense pink or red color indicating that the phenolphthalein equilibrium shifted to the left, producing more of the pink or red colored Hph.
The pink color in the solution fades. Some of the colored indicator ion converts to the colorless indicator molecule.
<h3>Explanation</h3>
What's the initial color of the solution?
is a salt soluble in water. dissociates into ions completely when dissolved.
.
The first test tube used to contain . is a weak base that dissociates partially in water.
.
There's also an equilibrium between and ions.
.
ions from will shift the equilibrium between and to the right and reduce the amount of in the solution.
The indicator equilibrium will shift to the right to produce more ions along with the colored indicator ions. The solution will show a pink color.
What's the color of the solution after adding NH₄Cl?
Adding will add to the concentration of ions in the solution. Some of the ions will combine with ions to produce .
The equilibrium between and ions will shift to the left to produce more of both ions.
The indicator equilibrium will shift to the left as the concentration of increases. There will be less colored ions and more colorless molecules in the test tube. The pink color will fade.
Well, think of it this way. If you put a big paper circle on the ground, and then you put smaller circles on top of the big circle, which one would have been there longer? The big circle, of course. So the same logic applies here: if the smaller craters had been older than the big crater, then when the big crater was formed, the smaller ones would've been buried. Therefore, crater 2 is older than the smaller craters inside it. Hope that helped! =)
Iron is constantly working to support life on Earth, from supplying plants with nutrients to serving as a key component of steel to carrying oxygen in your blood.
Iron is the most common metal, its pure form corrodes quickly when exposed to humid air and high temperatures.
it is abundant in the sun and stars.
It contributes to the synthesis of chlorophyll in plants.
It is a part of hemoglobin, a blood protein that transports oxygen from the lungs to the body's tissues in mammals.
The majority of it is used to create steel, an iron and carbon alloy used in manufacturing.
There are four main structural forms of iron, known as allotropic forms, in which atoms are bound in various ways.
These are few properties of iron that are unusual for metal.