Question | Answer |
The Atomic Radius (covalent radius) is ? | Half the distance between the nuclei of two atoms of the same element that are joined together by a single covalent bond |
Why do values of atomic radius increase down any one group in the Periodic table? | - A new shell further from the nucleus
- The screening effect of inner electrons |
Why do values of atomic radius decrease from left to right across any period of the Periodic Table? | - Increasing nuclear charge
- No increase in the screening effect |
The first ionisation energy is? | |
Why do the the values of ionisation energy decrease down the groups in the periodic table? | - Increasing atomic radius
- The screening effect of inner electrons |
Why do the values of ionisation energy increase across the periods in the Periodic Table? | - Increasing nuclear charge
- Decreasing atomic radius |
Why do the values of electronegativity decrease down the groups in the Periodic Table? | - Increasing atomic radius
- Screening effect of inner electrons |
Why do the Electronegativity values increase across the periods in the Periodic Table? | - Increasing nuclear charge
- Decreasing atomic radius |
What is the meaning of the term "Bond Length"? | The distance between the nuclei of two bonded atoms measured by x-ray diffraction |
What is 2nd Ionisation energy? | It’s the energy required to remove an electron from an ion with one positive charge in the gaseous state |
What does the term "n=3" refer to? | The Third Energy Level or Orbital |
The chemical properties of an element are largely determined by the? | Number of electrons in the Outermost Energy Level |
All the Alkali metals react with Oxygen to produce? | Metal Oxides |
Why is it important not to put Alkali metals into dilute acid? | An explosion occurs due to so much Hydrogen being produced |
An Alkali Metal + Water reacts to give? | |
What group number are the Halogens? | VII |
Do Halogens exist free in nature? | No |
What is the trend in reactivity of the Halogens | Reactivity increases as you go up the Group from Iodine to Fluorine |
More reactive Halogens will.? | Displace the less reactive Halogens from a solution of their ions |
What accounts for the increasing Boiling Points of the Halogens as you go down the group | Increasing Van Der Waals Forces due to increasing sizes of molecules |
Why do some elements have first ionisation energies that are much greater than expected | Atoms with filled and half-filled outer sub-levels have an increased stability leading to a greater 1st ionisation energy requirement |