The right answer is 2.
The number of protons contained in a nucleus (called an atomic number) is characteristic of a chemical element. For a given atomic number, the number of neutrons defines different "types" of this element: isotopes. The variation of the number of protons of the nucleus of an atom, during a nuclear reaction for example, causes a change of the element studied.
Answer:
B. A precipitate will form since Q > Ksp for calcium oxalate
Explanation:
Ksp of CaC₂O₄ is:
CaC₂O₄(s) ⇄ Ca²⁺ + C₂O₄²⁻
Where Ksp is defined as the product of concentrations of Ca²⁺ and C₂O₄²⁻ in equilibrium:
Ksp = [Ca²⁺][C₂O₄²⁻] = 2.27x10⁻⁹
In the solution, the concentration of calcium ion is 3.5x10⁻⁴M and concentration of oxalate ion is 2.33x10⁻⁴M.
Replacing in Ksp formula:
[3.5x10⁻⁴M][2.33x10⁻⁴M] = 8.155x10⁻⁸. This value is reaction quotient, Q.
If Q is higher than Ksp, the ions will produce the precipitate CaC₂O₄ until [Ca²⁺][C₂O₄²⁻] = Ksp.
Thus, right answer is:
<em>B. A precipitate will form since Q > Ksp for calcium oxalate</em>
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Argon has 24 known isotopes.
Answer:
Option (d) is correct
N³⁻ > F⁻ > Mg²⁺ > Si⁴⁺
Explanation:
Total electrons for all the species = 10
So these are <u>iso electronic</u> with each other.
We know
Ionic radii ∝ 
- Si⁴⁺ has 14 protons and 10 electrons
- Mg²⁺ has 12 protons and 10 electrons
- N³⁻ has 7 protons and 10 electrons
- F⁻ has 9 protons and 10 electrons
- Iso electronic species with greatest number of protons have small size and vice versa.
- So Si⁺⁴ have smallest size and N³⁻ have largest in size
The salt contains ionic bond so that it dissociate ultimately by the movement of ion electricity is conducted
