Sciencemadness Discussion Board

2 questions about Sulfuric Acid

PeteH - 15-10-2014 at 22:05

Very green here!
I have 2 questions regarding Sulfuric Acid which I'm using for mixing photographic bleach & Stop from scratch...

1. I need to put it in storage for a few months. They're in Glass Bottles. Is it ok for the bottles to be laying on their side (somehow I was suddenly concerned with their plastic bottle tops)

2. I have 1 type that says 95-98% and the other 95-97%. I was wondering if it's ok to mix these 2 types together. (I have some half full bottles and was going to consolidate for space purposes

Thank you

Actinium - 15-10-2014 at 22:25

I would always store your chemicals upright, especially Concentrated Sulfuric acid. I imagine that the cap is made for that particular chemical however you would not want it to eat through the cap and/or have it leak into the surrounding and come into contact with any wood or worse your other chemicals as this would be a fire or worse waiting to happen.
As far as mixing them, I can't really say other than they are 2 different concentrations so its definitely going to change its Percentage.

j_sum1 - 15-10-2014 at 22:34

Aside from the issues of pouring safely from one bottle to another. (I always pour acid slowly), there should be no problems in mixing the two. It is likely that they are manufactured to the same spec. There is no significant difference between 95-97% and 95-98%. You don't even know for certain which is more concentrated. The phase diagram ( illustrates the concentrations we are talking about and the reason why it is easier to purify to 95%.

Just pour carefully. Check your bottle can hold the total volume. Get your spill kit ready. Wear ppe including glasses.
And yes, store upright. Just a dribble from a bottle not properly sealed is going to cause you grief.

PeteH - 15-10-2014 at 23:18

Hi there,

Many thanks for your replies.
Much appreciated.