The order of placement of the elemnts on the modern Periodic Table is determinated by:
1)atomic number (Z=number of protons).
The relative molecular mass of acid A : 50 g/mol
<h3>Further explanation</h3>
Given
40.0 cm³(40 ml) of 0.2M sodium hydroxide
0.2g of a dibasic acid
Required
the relative molecular mass of acid A
Solution
Titration formula
M₁V₁n₁=M₂V₂n₂
n=acid/base valence(number of H⁺/OH⁻)
NaOH ⇒ n = 1
Dibasic acid = diprotic acid (such as H₂SO₄)⇒ n = 2
mol = M x V
Input the value in the formula :(1 = NaOH, 2=dibasic acid)
0.2 x 40 x 1 = M₂ x V₂ x 2
M₂ x V₂ = 4 mlmol = 4.10⁻³ mol ⇒ mol of Acid A
The relative molecular mass of acid A (M) :

Explanation:
a.
→ ?




Removing common ions from both sides, we get the net ionic equation:

b.
→

No precipitation is occuring.
c.
→




Removing common ions from both sides, we get the net ionic equation:

d.
→




Removing common ions from both sides, we get the net ionic equation:

Answer: A strong acid like HCl dissociates completely in an aqueous solution.
By definition a strong acid is that that dissociates completely in aqueous solutions. That means that all the molecules of the acid will be inoized into hydronium cation (H3O+) and anion (the negative radical).
For expample, HCl is a strong acid because
HCl + H2O----> H3O(+) + Cl-
The forwar arrow indicates that all the molecules of HCl reacted with the water for form the ions.
Electron Configuration is the distribution of electrons of an atom or molecule in an atomic or molecular orbitals.
So Na, or Sodium has 11 electrons, so the number should add up to 11
Na: 1s² 2s² 3p⁶ 3s¹
Hope this helps!