Iodine (iodine-potassium iodide) staining distinguishes starch ( a polysaccharide) from monosaccharides, a disaccharides and other polysaccharides. Therefore, a bluish black color is a positive test for starch, and a yellow-ish brown color ( no color change) is a negative test for starch.
Answer:
a. the mole fraction of CO in the mixture of CO and O2.
mole fraction = moles of CO/ Total moles of the mixture
Mole fraction of CO = 10/(10+12.5)=0.444
b. Reaction - CO(g)+½O2(g)→CO2(g)
Stoichiometry: 1 mole of CO react with 0.5mole of O2 to give 1 mole of CO2
So given,
At a certain point in the heating, 3.0 mol CO2 is present. Determine the mole fraction of CO in the new mixture.
3mol of CO2 is produced from 3 mols of CO and 1.5mol of O2
This means that unused mols are : 7mols of CO and 11mols of O2
Total product mixture = 3 + 7 + 11 = 21mols
mole fraction of CO = 7/21 = 0.33
For a given system, vapor pressure can be defined as the pressure exerted by the vapor phase in equilibrium with the condensed phase.
In this case, as water sits in an open beaker it tends to evaporate thereby forming water vapor. This vapor phase then exerts a pressure over the liquid water, which is termed as the vapor pressure of water at that temperature and pressure. As water continues to evaporate, more and more molecules escape into the vapor phase which thereby increases the vapor pressure.
Ans: The vapor pressure of water increases as the water evaporates.
Can you pick more than one?
Answer:
Option C
Explanation:
The answer is option C or "The amount of time it takes to rotate around it's axis is the same amount of time it takes to revolve around Earth."Remember that the Earth and the Moons amount of time to make a full rotation is almost in sync and they're two sides of the moon, one side we do not see and that's because that side is currently faced away from the Earth which is called the dark side of the moon. Each side has two weeks oh night, and two weeks of day because of how long it takes the moon to revolve, so while we have a side towards the Earth which is illuminated by the sun we have another pointing away in the dark.
Hope this helps.
