1. c. 35
2. <span>d. 1.26 x 10^24 molecules
3. </span><span>d. 303.6 g</span>
Answer:
D
Explanation:
beacause all the elements in period 3 has different valence electrons hence you look at the first element in period 3 is sodium which has a valence electron of 1 when you go across the period to the right their valence electron decreases to be negative
Answer:
<em>The pH of the solution is 7.8</em>
Explanation:
The concentration of the solution is 0.001M and the dye could be in its protonated and deprotonated forms. If the concentration of the protonated form [HA] is 0.0002 M the concentration of the deprotonated form will be the subtraction between the concentration of the bye and the concentration of the protonated form:
[A-] = 0.001M - 0.0002M = 0.0008M
Also, the Henderson-Hasselbalch equation is
![pH = pKa + Log \frac{[A^{-}]}{[HA]}](https://tex.z-dn.net/?f=pH%20%3D%20pKa%20%2B%20Log%20%5Cfrac%7B%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
this equation shows the dependency between the pH of the solution, the pKa and the concentration of the protonated and deprotonated forms. Thus, replacing in the equation
Answer:
Yes
Explanation:
A gene pool is the sum total of all the genes(sum of alleles)of a species and population at any given time is known as gene pool.
The new species are created in nature by four mechanisms such as geographic isolation (allopatric speciation), reproductive isolation (sympatric speciation), mating behaviour (parapatric speciation).
Due to any of these factors when population acquire unique changes in their genes and enough changes have been introduced in the gene pool of the population with time, two population become distinct from each other and not able to interbreed leads to the formation of new species.
Answer: B
Explanation: the moon is smaller and contains less mass, therefore its gravitational pull is less than that of Earth's.
