Neutral litmus paper is purple. Under acidic conditions, the solution is red, and under basic conditions, the solution is blue. Chemical reactions other than acid-base can also cause a color change to litmus paper. For instance, chlorine gas turns blue litmus paper white — the litmus dye is bleached ,  because of presence of hypochlorite ions. This reaction is irreversible, so the litmus is not acting as an indicator in this situation.
The litmus mixture has the CAS number and contains 10 to 15 different dyes. All of the chemical components of litmus are likely to be the same as those of the related mixture known as orcein , but in different proportions.
In contrast with orcein, the principal constituent of litmus has an average molecular mass of Azolitmin shows nearly the same effect as litmus.
Red litmus contains a weak diprotic acid. When it is exposed to a basic compound, the hydrogen ions react with the added base. The conjugate base, formed from the litmus acid, has a blue color, so the wet red litmus paper turns blue in alkaline solution. From Wikipedia, the free encyclopedia. Redirected from Litmus paper. For other uses, see Litmus disambiguation. For the political term, see Litmus test politics.
The acid in the vinegar breaks down the calcium carbonate of the shell, a process which you can see starting almost immediately when bubbles begin to form on the surface of the egg as it releases carbon dioxide. As you can see from the video, however, the egg is not indestructible.
A very cool experiment, but you have to plan ahead. Our next round of experiments required some red cabbage, which makes a handy pH indicator.
Simply slice some red cabbage, put it in a pot with just enough water to cover it, and simmer for 30 minutes or so. First, take smallish rectangles of paper we used index cards , and soak them in the cabbage juice then set them aside to dry. The acids will immediately turn the cabbage juice pinkish-purple, while the base will make the juice greenish-blue. Add an acid to one and a base to the other for example lemon juice and baking soda, respectively.
Your kids will be astonished at what happens. Now that the litmus paper is dry, cut it into strips and collect a selection of items from your fridge to test. We used the brine from olives, pickles, and spicy peppers, as well as apple juice and cola. The olives, having no vinegar in the brine, showed no change.
What do you think happened with the others? Simply take a few cups, put a centimeter or two of liquid in the bottom, and add a couple of copper coins to each one. If you can stand a few up against the edge so they are half-in-half-out, the result is even more dramatic. The acids dissolve the copper oxide on the surface of the coins, leaving them their original shiny selves. This might be a good time to point out to your children that what the cola does to the surface of the coins it also does to the surface of their teeth.
With a pH of about 3. Which you probably would hesitate to drink. With that it was time to bake cookies, have dinner, and run the bath, where our final experiment of the day took place. Take a small plastic drink bottle, and drill a hole in the cap. Using any narrow tube such as a straw I used the tube from a pen , thread it through the hole and take some modelling clay to seal both the inner and outer surfaces of your hole.
The weight of the clay also keeps the cap end of the bottle below water. Place it in the tub, and let go. For more ideas, here are 15 science experiments you can do with your kids. Have fun, and try not to blow anything up. Easy Science Experiments for Kids: These are just a lot of fun for kids, and you always end up learning a bit yourself along the way.
Acid - Base Indicators: The most common method to get an idea about the pH of solution is to use an acid base indicator. An indicator is a large organic molecule that works somewhat like a " color dye".
Read this essay on Acid Base. Come browse our large digital warehouse of free sample essays. Get the knowledge you need in order to pass your classes and more. Only at eclipsed.ml".
Wet litmus paper can also be used to test for water-soluble gases that affect acidity or alkalinity; the gas dissolves in the water and the resulting solution colors the litmus paper. For instance, ammonia gas, which is alkaline, turn the red litmus paper blue. View Essay - Acid Base Case Study eclipsed.ml from BSN at Grand Canyon. Running head: DEHYDRATION DANGERS Acid Base Case Study Paper Jennifer Childers Grand Canyon University: NURE January.
Astrobrights Galaxy Gold paper is the worlds largest acid/base indicator strip. Dip it in a base solution (like ammonia cleaner, baking soda in water, etc.) and it turns bright red. Dip it in acid (vinegar, lemon juice, etc.) and it turns yellow again. To see where this definition comes from, let’s look at the acid-base properties of water itself.