A way of building knowledge about the world around us through observation and experimentation.
Answer :
The concentration of 
before any titrant added to our starting material is 0.200 M.
The pH based on this ion concentration is 0.698
Explanation :
First we have to calculate the concentration of before any titrant is added to our starting material.
As we are given:
Concentration of HBr = 0.200 M
As we know that the HBr is a strong acid that dissociates complete to give hydrogen ion and bromide ion 
.
As, 1 M of HBr dissociates to give 1 M of
So, 0.200 M of HBr dissociates to give 0.200 M of
Thus, the concentration of before any titrant added to our starting material is 0.200 M.
Now we have to calculate the pH based on this ion concentration.
pH : It is defined as the negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)
Thus, the pH based on this ion concentration is 0.698
Answer:
A.The two ends are like poles
Explanation:
Magnets are composed of a north pole and a south pole. If two like poles of a magnetic are placed near each other, the two ends seem to push apart.
The reason for this is that, when like poles of two magnets are made to face each other, the lines of forces are in opposite directions, hence the magnets repel.
If unlike poles of two bar magnets are made to face each other, the magnetic lines of force are now in the same direction therefore the unlike poles attract each other.
Answer:
B. The [H1+] >[OH1-] and the solution is acidic
Answer: False
Explanation:
AC change directions and DC only flow in one direction
