Hydrion Buffer Capsules not dissolving easily in DI water

[dmcmillen]

I have some 4.0 and 7.0 Hydrion buffer capsules that I purchased in January of 2017. There are 5 bottles of 10 capsules of each buffer. There is no expiration date on the box or the bottles but I believe from another thread here that the 7.0 should be good for about 2 yrs and the 4.0 for 4 years. The problem I am having with them is it is very difficult to dissolve into the 100ml of room temp DI water. I can get dissolved but it is an effort. Is that an indication that they are no longer any good? Oh, they do test accurately once I can get dissolved.

 

[ajdelange]

I think this...

Oh, they do test accurately once I can get dissolved.

...answers...

Is that an indication that they are no longer any good?

I can't think why they might be so hard to dissolve. I have noticed that 7 buffer (I use Hach pillows) is a little more difficult to dissolve than the 4 and I used to use the Hydrion capsules but I don't remember them being any more difficult to dissolve than the Hach product. They should be the same chemicals (phosphate salts).[/QUOTE]

 

[dmcmillen]

Ah yes, did answer my own question. The only way I can dissolve is to crush the salts against the side of the glass I am using. I think I'll use some out of another tube next time and see if they're the same. I don't have enough data points right now. Just seeing if someone else has had this problem.

 

[flars]

These are the capsules? It will work better to open the capsule and pour the contents into the water.

 

[dmcmillen]

It will work better to open the capsule and pour the contents into the water.

Now that's funny! Of course, have to open the capsules and pour into water.

 

[dmcmillen]

flars, Didn't mean to be disrespectful. I just couldn't get this picture out of my head of trying to stir the capsule in the water.