The Periodic Table and Reactivity Series Flashcards
What is a particular property of all the noble gases (Group 0) and why are they like this?
The noble gases are inert (do not react) because they have a full outer shell and are stable.
Why do elements in the same group of the Periodic Table have similar chemical properties?
- Elements in the same group have the same number of electrons on their outer shell.
- This is because they will all lose/gain the same number of electrons to have a full outer shell (and become stable).
What happens when lithium, sodium or potassium react with water?
- They react vigorously to form a metal hydroxide and hydrogen.
- The fact that they react in the same way provides a basis to recognise these as a family of elements.
How does reactivity change for the elements in Group 1?
The further down the periodic table you go, the more reactive the element (i.e. lithium is the least reactive). Potassium is the most reactive (don’t need to know any further than potassium).
Why does the reactivity of lithium, sodium and potassium change as you go down the periodic table?
- Group 1 elements need to lose one electron to gain a full outer shell.
- As you go further down the periodic table, the reactivity increases because you there are more outer shells and the force holding the electron to the nucleus is weaker.
- Electrons can be lost more easily further down the group, so the elements will react more easily/vigourously.
What colour and state is chlorine at room temperature?
Chlorine is green and a gas.
What colour and state is bromine at room temperature?
Bromine is red/brown and a liquid.
What colour and state is iodine at room temperature?
Iodine is dark grey and a solid.
How would you predict the properties of some of the halogens (other than chlorine, bromine and iodine)?
- As the atomic number of the halogens increases, the elements get darker and have a higher boiling point.
What is the diference between hydrogen chloride gas and hydrochloric acid?
- Hydrogen chloride is a gas at room temperature.
- Hydrochloric acid is hydrogen chloride that has been dissolved in water.
- hydrochloric acid is HCl which has split up into H+ ions and Cl- ions
Why is hydrogen chloride not acidic in methylbenzene?
Methylbenzene is not polar, so when you dissolve hydrogen chloride in it, the HCl cannot dissociate into H+ and Cl- ions. There are no H+ ions, so it is not acidic.
Why is hydrogen chlorid acidic in water?
- When hydrogen chloride is dissolved in water. the HCl molecules split up into H+ and Cl- ions (dissociation).
- The presence of H+ ions eans that hydrochloric acid is an acidic solution.
What are the relative reactivities in the Group 7 elements?
Group 7 elements become less reactive as you go down the Periodic Table because when there are fewer outer shells, the pull of the nucleus is stronger so it is easier for electrons to be attracted.
What would happen if you reacted chlorine water with potassium iodide?
chlorine is higher up in Group 7 than iodine
The chlorine would react with the potassium in the potassium iodide to form potassium chloride.
displacement reaction - the iodine is displaced
What can displacement reactions also be described as?
e.g. Cl2 + 2KI → I2 + 2KCl
This is a redox reaction, since electrons are being passed from the iodine to the chlorine. Chlorine gains electrons, so is reduced and iodine loses electrons, so is oxidised.
