Answer:
Taxonomy
Explanation: Taxonomy formally names and classifies organisms by thier structure, function, and relationships
Answer:
The correct answer is B difficult to lose but easy to move.
Explanation:
Metals are chemical substances in which the electrons of the outer orbital or valence orbital are hold very tightly through intramolecular attraction by the nucleus present in the center of the atom of the metal.As a result it is very difficult to remove electron from the valence orbital of metal.
As electrons are hold very tightly by the nucleus of a metal,the electrons are present in very compact manner within metal which helps metal to be an excellent conductor.
Answer:
There are 21 prime numbers between 0 and 75.
Explanation:
2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73
Answer:
a)4.51
b) 9.96
Explanation:
Given:
NaOH = 0.112M
H2S03 = 0.112 M
V = 60 ml
H2S03 pKa1= 1.857
pKa2 = 7.172
a) to calculate pH at first equivalence point, we calculate the pH between pKa1 and pKa2 as it is in between.
Therefore, the half points will also be the middle point.
Solving, we have:
pH = (½)* pKa1 + pKa2
pH = (½) * (1.857 + 7.172)
= 4.51
Thus, pH at first equivalence point is 4.51
b) pH at second equivalence point:
We already know there is a presence of SO3-2, and it ionizes to form
SO3-2 + H2O <>HSO3- + OH-
[HSO3-] = x = [OH-]
mmol of SO3-2 = MV
= 0.112 * 60 = 6.72
We need to find the V of NaOh,
V of NaOh = (2 * mmol)/M
= (2 * 6.72)/0.122
= 120ml
For total V in equivalence point, we have:
60ml + 120ml = 180ml
[S03-2] = 6.72/120
= 0.056 M
Substituting for values gotten in the equation
We noe have:
=4.04
pH = 14- pOH
= 14 - 4.04
= 9.96
The pH at second equivalence point is 9.96