using what you know about the valence shells of the metals of the periodic table explain why sodium and potassium are most commonly found bound with halides while manganese and calcium are most commonly found bound with carbonatr
because of the electrons they share
K and Na don't share any electrons with anything.
To understand why sodium and potassium are commonly found bound with halides (such as chloride or fluoride) while manganese and calcium are commonly found bound with carbonates, we need to look at their respective positions in the periodic table and their valence shells.
Sodium (Na) and potassium (K) are both alkali metals, located in Group 1 of the periodic table. They each have one electron in their outermost shell. These valence electrons are relatively easy to remove, making sodium and potassium highly reactive.
Halides, on the other hand, are a group of elements that are a part of Group 17 of the periodic table, also known as the halogens. These elements have seven electrons in their outermost shell, so they are one electron short of having a complete octet. This makes them highly reactive and strongly desiring to gain one electron.
Due to the high reactivity of sodium and potassium, they readily donate their single valence electron to halides, such as chloride (Cl-) or fluoride (F-), which are in need of an extra electron. This forms ionic compounds, where the metal (Na or K) loses an electron (becoming Na+ or K+), and the halide gains an electron (forming Cl- or F-).
Now let's consider manganese (Mn) and calcium (Ca). Manganese is a transition metal found in the middle of the periodic table, while calcium is an alkaline earth metal, located in Group 2.
Manganese has multiple possible oxidation states, meaning it can lose different numbers of electrons. However, manganese often tends to have an oxidation state of +2 or +7. In the +2 state, manganese can form ionic bonds with carbonate (CO3^2-) ions, creating compounds like manganese(II) carbonate (MnCO3). In the +7 state, manganese can form covalent bonds and create compounds with carbonate, such as permanganate (MnO4^-).
Calcium, as an alkaline earth metal in Group 2, has two valence electrons. It readily loses these two electrons to achieve a stable octet configuration. Carbonate has a -2 charge, making it a suitable candidate for bonding with calcium. As a result, calcium carbonate (CaCO3) is commonly found, such as in limestone or eggshells.
In summary, the tendency of sodium and potassium to form ionic bonds with halides is due to their highly reactive nature and the need of halides to gain an electron. On the other hand, manganese and calcium tend to bond with carbonates due to their specific oxidation states and the preference of carbonates to accept electrons from these metals.