Excusme:
Can somone tell me what are alkalis and acids. I am doing a homework about acids and alkalis [level 3 to 6]. About level 3 is name some alkalis and aids and some everyday substance that contains acids. Level 4 is about know some acids and alkalis which are more dangerous than others and describe some everyday uses of acids. level 5 is about know what neutral substance is determined by ph scales know what is meant by neutralisation.
I'll just hit the highlights. If you want more information about a particular point just repost but explain in detail what information you need.
Alkali is just another word for base. In chemistry we have acids, bases, and salts (generally although some definitions just recognize acids and bases). An acid is a material, in the simple definition, that provides hydrogen ions in solution. Some common acids are citric (found in fruits such as lemons, oranges, etc) and generally have a sour taste. Tomato juicer is acidic, soft drinks are acid due to the carbonation (carbon dioxide under pressure). Acetic acid is the principal ingredient of vinegar. Most vinegar I see on the market is 4% or 5% acetic acid and there are a number of uses for vinegar in the home but most use vinegar that is dilutd significantly with water. None of those are dangerous, although I wouldn't want to get 5% vinegar in my eye or in an open cut. Other acids I have seen around the house are muriatic acid (another name for hydrochloric acid (HCl) that is not very pure). Muriatic acid is quite dangerous. I have also seen hydrofluoric acid (HF) sold under various trade names for removal of rust spots on carpets. Oxalic acid also removes rust spots and is sold by automotive supply houses for cleaning rust from radiators of automobiles. Both HF and oxalic acid, although not classified as strong acids, never-the-less, are dangerous.
Bases are defined in various ways but the simplest is that they produce hydroxide ions in solution. They are slippery to the touch. Many are common around the house and some are quite dangerous. I'm sure you have seen lye. Lye is essentially sodium hydroxide and it is very corrosive. It will put an eye out in 2-3 seconds. Many drain cleaners are lye (although there are some that are concentrated acids). All drain cleaners are dangerous. Most cleaning agents are mild bases. Chlorox and associated bleaching agents are, for many of them, acids but their danger comes from the bleaching action.
Finally, acids and bases neutralize each other. A common base that can be used to neutralize acids is baking soda. Soda is sodium hydrogen carbonate and it is the material that produces carbon dioxide by reacting with the acid in sour milk (lactic acid) when biscuits are made. Of course baking soda is safe. Another acid found in the home is cream of tartar but that is used in baking also.
I hope this is complete enough to answer your questions but not so wordy as to be overwhelming. Don't hesitate to ask for clarification.
sym
Certainly! I can help you with your homework about acids and alkalis. Let's start by understanding what they are.
Acids:
Acids are a type of chemical substance that, when dissolved in water, produce positively charged hydrogen ions (H+ ions). They have a sour taste and can react with metals to produce hydrogen gas. Examples of common acids include hydrochloric acid (HCl), sulfuric acid (H2SO4), and citric acid (found in citrus fruits).
Alkalis:
Alkalis, also known as bases, are substances that can neutralize acids. When alkalis dissolve in water, they produce negatively charged hydroxide ions (OH- ions). They have a bitter taste and feel slippery to the touch. Common alkalis include sodium hydroxide (NaOH) and potassium hydroxide (KOH).
Now, let's move on to the different levels of your homework:
Level 3:
To name some alkalis, you can mention substances like ammonia (NH3), sodium hydroxide (NaOH), and potassium hydroxide (KOH). Examples of everyday substances that contain acids are vinegar (acetic acid), lemon juice (citric acid), and soft drinks (phosphoric acid).
Level 4:
When it comes to the danger level of acids and alkalis, it depends on their concentration and how they are handled. For example, concentrated sulfuric acid is more dangerous than vinegar. It is important to follow safety protocols and handle any strong acid or alkali with caution.
Acids have several everyday uses. Some examples include:
- Ascorbic acid (vitamin C) is used as a preservative in food.
- Sulfuric acid is widely used in car batteries and as a component in the production of fertilizers.
- Nitric acid is used in the manufacturing of explosives and dyes.
Level 5:
A neutral substance on the pH scale is determined by a pH value of 7. The pH scale ranges from 0 to 14, with values below 7 being acidic, values above 7 being alkaline, and a pH of 7 being neutral. Neutralization is a chemical reaction that occurs when an acid and an alkali react to form a salt and water. This reaction helps to neutralize the acidic or alkaline properties of substances.
To summarize:
- Acids are substances that produce positively charged hydrogen ions (H+) when dissolved in water, have a sour taste, and can react with metals.
- Alkalis are substances that produce negatively charged hydroxide ions (OH-) when dissolved in water, have a bitter taste, and can neutralize acids.
- Some alkalis include ammonia, sodium hydroxide, and potassium hydroxide. Examples of everyday substances containing acids are vinegar, lemon juice, and soft drinks.
- The danger level of acids and alkalis depends on their concentration and handling.
- Acids have various uses, such as food preservation, battery production, and manufacturing explosives.
- A neutral substance has a pH value of 7 on the pH scale, and neutralization is a reaction that occurs when an acid and an alkali combine to form a salt and water.
I hope this helps! If you have any further questions, feel free to ask.