Answer:
7.54%
Explanation:
A hydrate is a salt that has molecules of water incorporated into the crystals. It is represented by the molecular formula of the salt followed by how many molecules of water it has: XY.nH₂O.
So, the mass of water in the sample will be the difference between the hydrate and the salt without water:
mass of water = 1.034 - 0.956 = 0.078 g
The mass percentage is the mass of water divided by the total mass, and then multiplied by 100%:
(0.078/1.034)x100%
7.54%
To calculate the number of moles, simply take the ratio of mass and molar mass. The molar mass of Iron (Fe) is equal to 55.85 g/mol.Therefore the total number of moles is:
moles Fe = 25.7 g / (55.85 g / mol)
moles Fe = 0.46 mole
Explanation:
What happens during gas exchange in the alveoli?
These are called alveoli. They inflate when a person inhales and deflate when a person exhales. During gas exchange oxygen moves from the lungs to the bloodstream. At the same time carbon dioxide passes from the blood to the lungs.
What is the role of alveoli in gas exchange?
The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out. Oxygen breathed in from the air passes through the alveoli and into the blood and travels to the tissues throughout the body.
Explanation:
Half life of zero order and second order depends on the initial concentration. But as the given reaction slows down as the reaction proceeds, therefore, it must be second order reaction. This is because rate of reaction does not depend upon the initial concentration of the reactant.
a. As it is a second order reaction, therefore, doubling reactant concentration, will increase the rate of reaction 4 times. Therefore, the statement a is wrong.
b. Expression for second order reaction is as follows:
![\frac{1}{[A]} =\frac{1}{[A]_0} +kt](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B%5BA%5D%7D%20%3D%5Cfrac%7B1%7D%7B%5BA%5D_0%7D%20%2Bkt)
the above equation can be written in the form of Y = mx + C
so, the plot between 1/[A] and t is linear. So the statement b is true.
c.
Expression for half life is as follows:
![t_{1/2}=\frac{1}{k[A]_0}](https://tex.z-dn.net/?f=t_%7B1%2F2%7D%3D%5Cfrac%7B1%7D%7Bk%5BA%5D_0%7D)
As half-life is inversely proportional to initial concentration, therefore, increase in concentration will decrease the half life. Therefore statement c is wrong.
d.
Plot between A and t is exponential, therefore there is no constant slope. Therefore, the statement d is wrong
