Answer: 2.8275grams
Explanation: A buffer is made btw a weak acid and it salt. In a solution made by dissolving a weak acid in solution, equilibrium is set up btw ionised and unionised ion. For Benzoic acid
C6H5COOH....> C6H5COO- + H+
Ka = [C6H5COO-] [H+]/ [C6H5COOH].......(1)
using Ka = 6.5× 10^-5, [C6H5COOH] = 0.02M. PH= - log[H+] ....> [H+]= 10^-4M.
Putting the values in(1)
[C6H5COO-]= 6.5× 10^-5 × 0.02/ 10^-4
[C6H5COO-] = 0.013M = Molarity of sodium benzoate
Mole(C6H5COONa) = 0.013 × Volume = 0.013mol/litre × 1.5 litre
Mole(C6H5COONa) = 0.0195mol
Mass(C6H5COONa) = 0.0195 × Molar mass
Mass(C6H5COONa) = 2.8275g
Answer:
(a) Ionic
(b) Nonpolar covalent
(c) Polar covalent
(d) Polar covalent
(e) Nonpolar covalent
(f) Polar covalent
<em>For those substances with polar covalent bonds, which has the least polar bond?</em> NO₂
<em>For those substances with polar covalent bonds, which has the most polar bond?</em> BF₃
Explanation:
<em>Are the bonds in each of the following substances ionic, nonpolar covalent, or polar covalent?</em>
The nature of a bond depends on the modulus of the difference of electronegativity (|ΔEN|) between the atoms that form it.
- If |ΔEN| = 0, the bond is nonpolar covalent.
- If 0 < |ΔEN| ≤ 2, the bond is polar covalent.
- If |ΔEN| > 2, the bond is ionic.
<em>(a) KCl</em> |ΔEN| = |EN(K) - EN(Cl)| = |0.8 - 3.0| = 2.2. The bond is ionic.
<em>(b) P₄</em> |ΔEN| = |EN(P) - EN(P)| = |2.1 - 2.1| = 0.0. The bond is nonpolar covalent.
<em>(c) BF₃</em> |ΔEN| = |EN(B) - EN(F)| = |2.0 - 4.0| = 2.0. The bond is polar covalent.
<em>(d) SO₂</em> |ΔEN| = |EN(S) - EN(O)| = |2.5 - 3.5| = 1.0. The bond is polar covalent.
<em>(e) Br₂</em> |ΔEN| = |EN(Br) - EN(Br)| = |2.8 - 2.8| = 0.0. The bond is nonpolar covalent.
<em>(f) NO₂</em> |ΔEN| = |EN(N) - EN(O)| = |3.0 - 3.5| = 0.5. The bond is polar covalent.
Hello!
Like many other elements in chemistry, when an atom's valence shell is filled the element becomes stable. Through the octet rule we know that when the very last valence shell becomes filled, the atom is stable and therefore it is highly unlikely for the element to form bonds with that of another.
I hope this helped!
<span> (0.20948 x 31.998) / (
(0.78084 x 28.013) +
(0.20948 x 31.998) +
(0.00934 x 39.948) +
(0.000375 x 44.0099) +
(0.00001818 x 20.183) +
(0.00000524 x 4.003) +
(0.000002 x 16.043) +
(0.00000114 x 83.80) +
(0.0000005 x 2.0159) +
(0.0000005 x 44.0128) ) = 0.23140 = 23.140% O by mass </span>