How can you test if a given colourless liquid is an acid or a base without touching it?
Mhando fool hot after touching the hot obiect?
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Answers
Answer:
hiw can fell you test if a guven colourless loquid
Answer:
To determine whether a substance is an acid or a base, count the hydrogens on each substance before and after the reaction. If the number of hydrogens has decreased that substance is the acid (donates hydrogen ions). If the number of hydrogens has increased that substance is the base (accepts hydrogen ions).
Mix a sample of the liquid with a known acid. Acids and bases are well known for neutralizing each other on contact. This neutralization reaction can be recognized because it releases heat and gas, which causes the two reactants to fizz. Choose a well known, safe acid to do this reaction. Put a sample of your liquid into a bowl or dish. Add your acid with a dropper. If you see fizz forming in the bowl, your liquid is most likely a base,be sure that it's a dilute acid
Mix a sample of the liquid with a known base. Add the base to a bowl and then add your liquid to the base with a dropper. If you see the fizzing and bubbling of a neutralization reaction, your liquid is most likely an acid. There is no need to use a strong base. Something like baking soda will work well.
Choose an indicator. An indicator is a chemical (usually a type of dye) that will change colors predictably when exposed to an acid or base. Litmus will turn from blue to red in the presence of acid and from red to blue in the presence of a base. Red cabbage juice contains chemicals known as anthocyanins that turn red when exposed to acid, blue when exposed to bases, and yellow when exposed to a strong base.
your indicator can be in a liquid form, or you can use strips of paper coated with the indicator, known as pH strips.
Expose the indicator to a sample of liquid. If you choose to use pH strips, simply dip the strip into the liquid. Allow the strip to air dry momentarily. If you choose to use a liquid indicator, put the indicator in a clear container (so that you do not distort the color). Add the sample liquid to the indicator by dropping it in with a dropper
Observe the color change. Whether you use the pH strips or the liquid indicator, the color change should be the same. Some indicators, such as litmus, will only tell you if your solution is an acid or a base. Other indicators, such as red cabbage juice, can be compared to a universal indicator that will give you an approximate pH range of your liquid
Choose a pH meter. There are several different methods of measuring pH. The hydrogen electrode method is considered the most accurate standard, but is inconvenient for most applications. The most commonly used method is the glass diode method. It is easy to use and you get the same results (or close) each time you use it. If you are using very small sample sizes, you might consider a semi-conductor type pH meter.
Prepare your liquid. You want to make sure that your sample is as close to uniform as possible. Shake or stir the sample before measuring with the pH meter. Be sure that there are no solid particles in your sample, and that the sample is at a stable temperature. This way you will get the most accurate reading.
I hope it helps you...