Acids, Bases, PH Introduction.
This experiment helped to understand difference between acid and base and there PH levels. We learned how to identify buffer. Buffer is substances that resist changes in PH when acid or base is added to solution. Also we learned that water is neutral. Its mean that water has an equal concentration of H and OH. PH number of water is 7. Acid’s PH numbers less than 7. Bases’ PH number is greater than 7. As well we learned how to use and calibrate PH Meter. Materials and methods.
For experiment at class we used two solutions, solution A and solution B.
First we took PH meter and measured PH level of solution A. After we add to solution A 1.0ml of HCl and record PH level. Total of HCl added was 10 ml, we did it by adding 1.0 ml of HCl at the time.
Second time we took solution A and start adding 10 ml(1.0 ml at the time) of NaOH. With PH meter we record number changing in PH.
Third time we took solution B , measured PH level and did the same steps as with solution A.

Results.
Solution A. ml of acid or base added 1 2 3 4 5 6 7 8 9 10
HCl 6.95 6.91 6.92 6.93 6.91 6.90 6.88 6.88 6.87 6.88
NaOH 6.99 6.99 7.02 7.01 7.02 7.01 7.02 7.03 7.06 7.07

Solution B. ml of acid or base added 1 2 3 4 5 6 7 8 9 10
HCl 3.3 3.0 2.82 2.68 2.60 2.46 2.41 2.37 2.33 2.30
NaOH 9.95 10.23 10.48 10.38 10.66 10.70 10.83 10.88 10.89 11.09

Discussion.
From the table and graph we can see that solution A didn’t have big change in PH level number when HCl and NaOH were added. This is meant that solution A is