Answer:
0.0693M Fe
Explanation:
It is possible to quantify Fe in a sample using Mn as internal standard using response factor formula:
F = A(analyte)×C(std) / A(std)×C(analyte) <em>(1)</em>
Where A is area of analyte and std, and C is concentration.
Replacing with first values:
F = 1.05×2.00mg/mL / 1.00×2.50mg/mL
<em>F = 0.84</em>
In the unknown solution, concentration of Mn is:
13.5mg/mL × (1.00mL/6.00mL) = <em>2.25 mg Mn/mL</em>
Replacing in (1) with absorbances values and F value:
0.84 = 0.185×2.25mg/mL / 0.128×C(analyte)
C(analyte) = <em>3.87 mg Fe / mL</em>
As molarity is moles of solute (Fe) per liter of solution:
= <em>0.0693M Fe</em>
Answer:
Second option
Explanation:
We started using fossil fuels which are the main cause of climate change
Osmosis is the diffusion of water <span>across a semipermeable membrane (usually cell membrane) from a region of low solute concentration to a more concentrated solution so it can reach equilibrium (balance).
D</span>iffusion is <span>a spontaneous movement of particles from an area of high concentration to an area of low concentration.
Both results in particles moving and help balance out the concentrations.
Also, in osmosis, the water molecules are moving. In diffusion, it is the solutes moving.
I hope this helps and explains well.</span>
Answer:
(iii) A has pH greater than 7 and B has pH less than 7
Explanation:
Phenolphthalein is a common indicator in acid base titrations. It turns pink in basic conditions and turns colorless in acidic conditions. Thus on addition of solution A it becomes pink so A should be basic having pH more than 7. On addition of B , it turn out to be colorless means that B is an acidic solution having pH less than 7.
4 protons the number of proton has the same number of electron [which is the same as atomic number]