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True or false? Ammonia is a base since the molecule can pick up a hydrogen ion.
Ah, now that I've put some sugar in the lemon juice, it's not as acidic. Hellooo! Haven't you been listening? It's not the taste that determines the acidity. Let's run through it one more time: That the lemon juice is acidic means that it contains a lot of hydrogen ions, compared to pure water.
Adding sugar doesn't change that, it only hides the acidic taste. Okay, okay, I get it! The sugar doesn't change the amount of hydrogen ions in the lemonade. If I want to remove the acidity, then what should I add... to get rid of the hydrogen ions?
Then you'll have to add something that is the opposite of an acid - you need to add a base. Jenny is quite right. A base is the opposite of an acid. Acids are substances that release hydrogen ions. Bases can react with hydrogen ions, bonding to them.
Take a look at this - a hydrogen atom and an oxygen atom attached to each other - a hydroxide ion. If we add hydroxide ions to an acid... The hydroxide ions will pick up the free hydrogen ions, forming - water. The hydrogen ions aren't free in the solution - the solution is not as acidic as before. All substances containing hydroxide ions are bases.
One example is sodium hydroxide, that's used as a drain cleaner. However - a substance doesn't have to contain hydroxide ions to be a base. The important factor is the ability to pick up hydrogen ions. Like this gas - ammonia. It has one nitrogen atom and three hydrogen atoms.
Just like the hydroxide ion, the ammonia molecule can add one more hydrogen. This means that if ammonia is added to an acid, it decreases the amount of free hydrogen ions - ammonia is a base. Okay then, I'll just use some drain cleaner in the lemonade to make it less acidic! No Michael, stop! That's much too strong to be used in cooking.
You could damage your mouth. Maybe you've got some bicarbonate? That's used in baking as a leavening agent. It's not as strong as ammonia or sodium hydroxide, but it has the same effect: The hydrogen ions from the acid are picked up by the bicarbonate... Congratulations, now the lemon juice isn't as acidic anymore!
No, but now it tastes awful!