Answer:
pH=4.05
Explanation:
C7H6O2 -> C7H6O- + H+
ka= [C7H6O-] [H+]/[C7H6O2]
During equilibrium
[C7H6O-]= [H+]= x^2
[C7H6O2]=0.12-x
Replace
ka= x^2/0.12-x
6.5 x10^-5= x^2/0.12-x
7.8x10^-6 - 6.5 x10^-5x=x^2
x^2+ 6.5 x10^-5x - 7.8x10^-6
Solution of quadratic equation
x=8.8 x10^-5
pH= -log [H+]= -log 8.8 x10^-5=4.05
Answer:
Check explanation.
Explanation:
Electron affinity simply means the ability of an atom to gain an electron. Electron affinity can also be defined as the change in energy of a neutral atom in the gaseous phase when an electron is added to the atom to form a negative ion.
Electron affinity characteristics trends is that it increases upward for the groups and from left to right across periods of a periodic chart.
Both Bromine and Iodine are both found in group 7/17 , that is the Halogens on the periodic chart. Group seven element has 7 valence electrons(that is, it remains 1 electron for them to reach their octet). Hence, when an electron is added to these Halogens, energy will be released.
WHAT CAUSES THE DIFFERENCES in ELECTRON AFFINITY for bromine and IODINE are;
(1). Atomic size: iodine atom is larger than a bromine atom. Therefore, outermost electrons of Iodine are located further away from the nucleus.
(2). The shielding effect: Iodine has an extra full shell of core electrons between the nucleus and the outermost shell and these extra core electrons will shield the outermost electrons from the nucleus.
So, less energy will be released when one mole of electrons is added to one mole of Iodine atoms as compare with Bromine atoms
Answer : The oxidation state of Mg in Mg(s) is (0).
Explanation :
Oxidation number or oxidation state : It represent the number of electrons lost or gained by the atoms of an element in a compound.
Oxidation numbers are generally written with the sign (+) and (-) first and then the magnitude.
Rules for Oxidation Numbers are :
The oxidation number of a free element is always zero.
The oxidation number of a monatomic ion equals the charge of the ion.
The oxidation number of Hydrogen (H) is +1, but it is -1 in when combined with less electronegative elements.
The oxidation number of oxygen (O) in compounds is usually -2.
The oxidation number of a Group 17 element in a binary compound is -1.
The sum of the oxidation numbers of all of the atoms in a neutral compound is zero.
The sum of the oxidation numbers in a polyatomic ion is equal to the charge of the ion.
The given chemical reaction is:
In the given reaction, the oxidation state of Mg in Mg(s) is (0) because it is a free element and the oxidation state of Mg in is (+2).
Hence, the oxidation state of Mg in Mg(s) is (0).
Explanation:
Mg+NaF. NaF+Mg
are use sure about the question
Answer:
a. withdraws electrons inductively
b. donates electrons by hyperconjugation
c. donates electrons by resonance
d. withdraws electrons inductively
Explanation:
a. The bromide ion is a highly electronegative ion (in the halide series). Electronegative substituents on acids increase the acidity by inductive electron withdrawal method. The higher the electronegativity of a substance, the greater the acidity. The halogens have this order of electronegativity:
F > Cl > Br>I
b. The carboxyl groups have a stabilization of the sigma and pi bonds. This is achieved through a special delocalization of electrons. Because of the delocalization, hyperconjugation is the result effect.
c. The NHCH₃ group has a highly electonegative nitrogen atom that pulls the electron cloud towards itself. In this case, it withdraws electrons inductively. As a result, it donates electrons by resonance.
d. The OCH₃ group has a highly electonegative oxygen atom. This oxygen atom withdraws electron cloud towards itself. As a result, it withdraws electrons inductively.