Answer:
2
Explanation:
The atom shown in the image has 2 core electrons.
Electrons are the negatively charged particles within an atom. Therefore the total number of electrons surrounding the nucleus in the given specie is 7.
So;
We have 2 core electrons
And 5 valence electrons
The core electrons are the inner orbital electrons.
The valence electrons are the outermost electrons.
Answer:
Strontium, a group 2 element with an electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² , will form a +2 ion in a chemical bond.
Explanation:
An ionic bond is produced between metallic and non-metallic atoms, where electrons are completely transferred from one atom to another. During this process, one atom loses electrons and another one gains them, forming ions. Usually, the metal gives up its electrons forming a cation to the nonmetal element, which forms an anion.
So an ion is an atom or group of atoms that have an electric charge. A cation is an ion that has a positive charge.
The alkali metals in the earth (Elements IIA) lose two electrons to form a 2+ cation. Strontium is an alkali metal that loses the two electrons belonging to 5s², forming the +2 ion.
Percentage Yield = (Actual Yield ÷ Theoretical Yield) × 100
The Actual Yield is given in the question as 21.2 g of NaCl. However, in order to find the theoretical yield, you have to write a balanced equation and use the mole ratio to calculate the mass of NaCl that would be produced.
Balanced Equation: CuCl + NaNO₃ → NaCl + CuNO₃
Moles of CuCl = Mass of CuCl ÷ Molar Mass of CuCl
= 31.0 g ÷ (63.5 + 35.5)g/mol
= 0.31 mol
the mole ratio of CuCl to NaCl is 1 : 1,
∴ if moles of CuCl = 0.31 mol,
then moles of NaCl = 0.31 mol
Now, Mass of NaCl = Moles of NaCl × Molar Mass of NaCl
= 0.31 mol × (23 + 35.5) g/mol
= 18.32 g
⇒ the THEORETICAL Yield of NaCl, in this case, is 18.32 g.
Now, since Percentage Yield = (Actual Yield ÷ Theoretical Yield) × 100
⇒ Percentage Yield of NaCl = (21.2g ÷ 18.32g) × 100
= 115.7 %
NOTE: Typically, the percentage yield of a reaction is less than 100%, however in a case where the mass of the substance is weighed with impurities, then that mass may be in excess of 100% as seen here.
You did not provide any options.
K(eq) = concentration of products/concentration of reactant = [Cu+2] / [Ag+]^2
Activity of pure solid and liquid is taken as 1.
Hence last option is correct.
Hope this helps, have a great day ahead!
I hope this helps you alot
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