Answer:
Explanation:
Ca(In)²⁺ + EDTA → Ca(EDTA)²⁺ + In
We use the volume of EDTA consumed in the titration to <u>calculate the moles of Ca⁺² ions</u>:
- 0.012 L * 0.0600 M *
= 7.20x10⁻⁴ mol Ca⁺²
Now we <u>calculate the molarity</u>:
- 7.20x10⁻⁴ mol Ca⁺² / 0.050 L = 0.0144 M
To calculate in ppm, we <u>use the moles of Ca⁺² and convert to mg of CaCO₃:</u>
- 7.20x10⁻⁴ mol Ca⁺² = 7.20x10⁻⁴ mol CaCO₃
- 7.20x10⁻⁴ mol CaCO₃ * 100g/mol *
= 72 mg CaCO₃
Finally, <u>the concentration in ppm</u> is:
- 72 mg CaCO₃ / 0.050L = 1440 ppm
Answer:
15.5 gm
Explanation:
What is the mass of phosphorus that contains twice the number of atoms found in 14 g of iron?
[Relative atomic mass : P = 31; Fe = 56]
14 gm Fe = 14gm/ 56 gm/mole = 14 mole gm/56gm = 14/56 mole
0.25 moles
2 X 0.25 = 0.5 moles
1 mole P = 31 gm
so
0.5 moles P =31/2 =15.5 gm
External fertilization in animals usually occurs in water or in damp areas in a process called spawning.
Physicist Ernest Rutherford<span> established the nuclear theory of the atom with his </span>gold-foil experiment<span>. When he shot a beam of alpha particles at a sheet of </span>gold foil<span>, a few of the particles were deflected. He concluded that a tiny, dense nucleus was causing the deflections.</span>
