what is a buffer solution made of

4:33

1:11

5:21

کوتاه

15:50

7:19

10:19

4:55

17:02

4:44

2:33

9:16

16:01

30:29

14:42

8:15

5:02

34:18

2:04

5:50

14:34

3:58

3:59

4:04

3:45

4:00

4:00

4:21

2:28

1:57

1:51

3:49

3:47

10:26

3:46

3:47

13:06

3:38

4:21

12:15