It's easier for halogens to gain an electron than to let seven electrons go to become reactive.
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The further down the column you go the more electron shells in between the nucleus and the outside shell there are and so it has less 'pulling power' to grab that extra electron.
The Halogens are the most reactive non-metals. However, their reactivity decreases as you go down the group. Most reactive Fluorine>Chlorine>Bromine>Iodine>Astatine Least reactive. However, Astatine is not fully characterised because it is radio-active, and consequently is not found in open(school) labs.
0.79
To round look at the place value column to the right of the ten thousands column (the thousands column) - if it is 5 or more, the number rounds up, otherwise it rounds down. In 527,040 the thousands column is 7 which is 5 or more, so it rounds up. 527,040 → 530,000 to the nearest ten thousand.
Whether to round up or down depends on the digit in the units column. If the unit value is less than 5, you round down, if the unit value is 5 or above, round up. For example: 12 (The unit column contains a 2, which is less than 5, so round down) becomes 10 15 (The unit column contains a 5, which is 5 or above, so round up) becomes 20
To round to a place value column, look at the next column to the right: if it is 5 or more round up otherwise round down. To the nearest thousand look at the hundreds column. In this case it is 0, so the number rounds down: 8053 → 8000 to the nearest thousand.
The reactivity of Group 7 halogens decreases as you move down the column from fluorine to iodine. This is because atomic size increases down the group, leading to weaker intermolecular forces of attraction between atoms. As a result, it becomes harder for the halogens to gain an extra electron and they become less reactive.
Halogens become less reactive as you go down the group. This is because atomic size increases down the group, making it more difficult for the larger atoms to gain electrons and react with other substances. Conversely, smaller halogen atoms are more reactive because they can more easily gain electrons and form bonds with other elements.
The Halogens are the most reactive non-metals. However, their reactivity decreases as you go down the group. Most reactive Fluorine>Chlorine>Bromine>Iodine>Astatine Least reactive. However, Astatine is not fully characterised because it is radio-active, and consequently is not found in open(school) labs.
Halogens have high reactivity because they have a strong tendency to gain an electron to achieve a stable electron configuration. This reactivity decreases as you move down the group from fluorine to iodine.
Atoms with fewer electrons tend to be more reactive because they are more likely to gain additional electrons to achieve a stable electron configuration. This process allows them to become more chemically stable, leading to increased reactivity.
Group 8A elements, also known as noble gases, are colorless, odorless, and tasteless gases. They have a full valence shell of electrons, making them stable and unreactive. Their boiling points and melting points increase as you move down the group.
The halogens are the highly reactive nonmetals on the periodic table. This group includes elements such as fluorine, chlorine, bromine, and iodine, which readily form compounds with other elements due to their strong tendency to gain an electron.
The reactivity of halogens decreases down the group, which means Fluorine is the most reactive halogens as it is the most electronegative elements among the halogens, and also the Periodic Table.
more reactive
Fluorine (F) is the most reactive element in group 7A (also known as group 17 or the halogens). It has a strong tendency to gain an electron to achieve a stable octet configuration, making it highly reactive.
The most reactive group of metals in the periodic table is Group 1, the alkali metals. These metals are highly reactive due to their low ionization energies, which means they readily lose their outermost electron to form positive ions. This reactivity increases as you move down the group due to the decreasing ionization energies.
Reactivity generally decreases as you move down the halogen group from fluorine to astatine. This is due to the increase in atomic size and the shielding effect from additional electron shells, which results in weaker attraction for electrons and reduced reactivity. Fluorine is the most reactive halogen, while astatine is the least reactive.