What is the difference between a group and a family?
Table of Contents
What is the difference between a group and a family?
For the most part, element families and element groups are the same things. Both describe elements that share common properties, usually based on the number of valence electrons. Usually, either family or group refers to one or more columns of the periodic table.
Why do halogens get darker down the group?
From the lowest boiling and melting point to the highest, the group in order is fluorine, chlorine, bromine, iodine and astatine. As you move down the group the halogens become darker in colour. Fluorine has the highest effective nuclear charge, as the outer electrons have little shielding from inner electrons.
How do you predict boiling points?
3 Trends That Affect Boiling Points
- The relative strength of the four intermolecular forces is: Ionic > Hydrogen bonding > dipole dipole > Van der Waals dispersion forces.
- Boiling points increase as the number of carbons is increased.
- Branching decreases boiling point.
What happens to the reactivity as you go down Group 7?
Reactivity decreases down the group. This is because group 7 elements react by gaining an electron. As you move down the group, the amount of electron shielding increases, meaning that the electron is less attracted to the nucleus.
What happens to reactivity down Group 0?
The group 0 elements are placed in the rightmost column of the periodic table. They are called the noble gases because they are all chemically unreactive (the term noble in chemistry signifies a lack of chemical reactivity)….Chemical Symbols:
| Element | Symbol | Atomic No. |
|---|---|---|
| Argon | Ar | 18 |
| Krypton | Kr | 36 |
| Xenon | Xe | 54 |
| Radon | Rn | 86 |
Do Group 7 elements lose or gain electrons when they react?
The reactivity of Group 7 elements decreases down the group. Non-metal atoms gain electrons when they react with metals. The electrons in the outer shell move further away from the nucleus as we go down the group and the attraction force between the electrons and the nucleus become weaker and weaker.
Why do the elements get more reactive as you go down Group 1?
All group 1 metals have one electron in its outer shell. As we go down the group, the atom gets bigger. Therefore, the attraction between the nucleus and the last electron gets weaker. This makes it easier for the atom to give up the electron which increases its reactivity.
Is Group 1 or 7 more reactive?
A useful mnemonic picture to help you recall that: As you go down group 1 (the alkali metals) in the periodic table, the elements get more reactive. As you go up group 7 (the halogens), again the elements get more reactive.
Why does potassium melt into a ball?
Sodium also floats on the surface, but enough heat is given off to melt the sodium (sodium has a lower melting point than lithium and the reaction produces heat faster) and it melts almost at once to form a small silvery ball that dashes around the surface….
| enthalpy change (kJ / mol) | |
|---|---|
| K | -196 |
| Rb | -195 |
| Cs | -203 |
Does reactivity increase left to right?
Chemical reactivity of the elements – definition Period – reactivity decreases as you go from left to right across a period. The farther to the left and down the periodic chart you go, the easier it is for electrons to be given or taken away, resulting in higher reactivity.
How can you tell which element is more reactive?
The number of electrons in the outermost shell of an atom determines its reactivity. Noble gases have low reactivity because they have full electron shells. Halogens are highly reactive because they readily gain an electron to fill their outermost shell.
