Answer:
D. Atoms are like solid balls
Explanation:
John Dalton proposed that all matter is composed of very small things which he called atoms. This was not a completely new concept as the ancient Greeks (notably Democritus) had proposed that all matter is composed of small, indivisible (cannot be divided) objects. When Dalton proposed his model electrons and the nucleus were unknown.
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
N -3
Ba +2
Sr +2
F -1
I -1
Ca +2
Mg +2
S -2
S -2
Al +3
//
Ba3N2
SrF2
CaI2
MgS
Al2S3
//
I don't really understand 2.
Answer:
yes the one that is circled is correct
Explanation: