Answer:
The group number in the periodic table represents number of valence electrons of the elements in a certain group.
Explanation:
There are s, p, d, and f blocks, which you can see in periodic table
The s-block and p-block together are usually considered main-group elements, the d-block corresponds to the transition metals, and the f-block encompasses nearly all of the lanthanides (like lanthanum) and the actinides (like actinium)
There are three main principles, which may useful for you:
- The Pauli exclusion rule basically says that at most, 2 electrons are allowed to be in the same orbital.
- Hund’s rule explains that each orbital in the subshell must be occupied with one single electron first before two electrons can be in the same orbital.
- The Aufbau process describes the process of adding electron configuration to each individualized element in the periodic table.
Hope this helps!
The correct answer is a. This is because the pH of a solution is defined as -log10(concentration of H+ ions). An inverse logarithmic scale such as this means that a solution with a lower concentration of H+ ions will have a higher pH than one with a higher concentration. Therefore we know that the pH of the second sample will be higher than the first.
Since the logarithmic scale has the base 10, a change by 1 on the scale is a consequence of multiplication/division of the H+ concentration by a factor of 10. As the scale is inverse, this means that a decrease of concentration by factor 1000 is equivalent to increasing the pH by (1000/10) = 3.
Answer : The time taken for the reaction is, 28 s.
Explanation :
Expression for rate law for first order kinetics is given by :
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 0.0632
t = time taken for the process = ?
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount or concentration of the reactant = 1.28 M
![[A]](https://tex.z-dn.net/?f=%5BA%5D)
= amount or concentration left time 't' = 
Now put all the given values in above equation, we get:
Therefore, the time taken for the reaction is, 28 s.
<span>rutherfordium element # 104</span>
Answer:
nucleus
Explanation:
Electrons are found in clouds that surround the nucleus of an atom. Those clouds are specific distances away from the nucleus and are generally organized into shells. Because electrons move so quickly, it is impossible to see where they are at a specific moment in time.
