That smells like it tastes good…!

Yum, chips !
Yum, chips !

Have you ever smelt a lip balm, Vaseline or hair product that, when you smelt it , it was as if you could almost taste it? Have you ever wondered why you can never really taste food when you have a cold? These are questions that have puzzled me in the past, but not anymore as…
There’s a reason why this happens!

When you eat food, take for example chicken and chips, you put them into your mouth and simply chomp and chew. There are little dots on your tongue called papillae, which you can find by looking at your tongue in the mirror. Papillae are made up of many taste buds which send information to your brain about how the food you eat tastes (e.g. salty, savoury, sweet, etc.)


Papillae dots on the tongue.
Papillae dots on the tongue.

As this is happening, smell molecules (also known as odour molecules) travel up from inside your mouth to the nose to the nasal cavity or into straight from up your nose. At the top of the nasal cavity are receptors (proteins) which the odour molecules bind, or in other words stick, to. A message is then sent to your brain which provides more information to the brain what exactly you’re eating, which is probably the fish you’ve moved on to after you’d just finished your chips

When your nose is blocked by snot when you have a cold, most of the odour molecules released from the food are prevented from reaching the olfactory receptors in the nose , only a few lucky ones make it up there, so that when you taste food .Well, you can barely, if not, taste it.



What is ionic bonding I hear you cry ?…

sodium and chlorine ions

Key terms:

Anion, cation, ionic bonding, electrostatic attraction

Ionic bonding is types of bonding that takes place between metal and non-metal atoms. These then form oppositely charged ions that experience an electrostatic attraction called ionic bonding.

When a metal and non-metal interact, the metal atom loses electrons to form positively charged ions. The metal ions are positively charged as they contain fewer electrons, that are negatively charged, than protons in the nucleus, that are positively charged, so the overall charge of the atom is positive and charged particles, which in this case is a positively charged one, are called ions.

So, metal ions form positively charged ions, called cations, while non-metal atoms gain electrons, forming negatively charged ions (anions). These two ions are oppositely charged and experience electrostatic attraction (attraction between oppositely charged ions) .This attraction is called ionic bonding.

Why do atoms give and get electrons like it’s the Christmas holidays, you may wonder?

Well, let’s take the Sodium and chlorine atoms in the picture above this blog post. Both atoms need to have the electronic configuration of a noble gas (inert gas configuration). This means the number of electrons surrounding the nucleus must be the same as that of a noble gas. In order for this to happen, metal ions lose electrons for an inert gas configuration while non-metal atoms become negatively charged ions by gaining electrons, and forming an inert gas configuration also.

So, let’s look at the diagram of Sodium and chlorine again. The sodium atom has an outermost shell occupied by one electron so loses 1 electron to form an ion with a single negative charge and will now have 2 electrons in its first shell and 8 in its second shell. Now look at the periodic table, if you have one, at Neon. It has the same number of electrons as the Na+ ion has so will also, like the Sodium ion, have 2 electrons in its first shell (energy level) and 8 electrons occupying its second shell.

SEE? The electronic configuration of the Sodium ion is the same as that of the Noble gas! Chlorine gains electrons also to become a negatively charge ion, with a 1- charge and the electronic configuration of the noble gas Argon (basically, has the proton number as the noble gas Argon).

Salt on chips is made from this.. Ionic bonding!
Salt on chips is made from this… Ionic bonding!