Answer:
Knowing that boron has an atomic mass of 10,811 means that all boron isotopes on average weigh 10,811 u.
Explanation:
The atomic mass of an atom is the mass of the atom measured in u (unified atomic mass unit), although we can also express it as Da (Dalton's unit)
Atomic mass refers to the average mass that all isotopes of that element have.
When we speak of isotopes we are referring to the element itself but with a different number of neutrons, which makes it modify its mass number.
Answer: The value of the pH is 8.58
Explanation:
The pH is defined negative logarithm of the 
ions concentration in a given solution.
![[H^+]=2.6\times 10^{-9} M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D2.6%5Ctimes%2010%5E%7B-9%7D%20M)
![pH=-\log[2.6\times 10^{-9}]=5.58](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B2.6%5Ctimes%2010%5E%7B-9%7D%5D%3D5.58)
The value of the pH is 8.58
Answer:
An open circuit is one where the continuity has been broken by an interruption in the path for current to flow. A closed circuit is one that is complete, with good continuity throughout. A device designed to open or close a circuit under controlled conditions is called a switch.
Elements in the same column of the periodic table exhibit similar properties (periodicity). Carbon, in Group XIV (14), and elements below it in the same column react in similar fashion. The most similar element to carbon is silicon (Si).
