Group 17 elements, known as halogens, are nonmetals. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine a solid. Astatine is a highly unstable radioactive element, so currently, most of its properties are unknown due to its short half-life. Tennessine is a synthetic element also predicted to be in this group. 

Minerals are essential nutrients that the human body needs in small amounts to work properly. They play a vital role in many bodily functions, such as building strong bones and transmitting nerve impulses. Some minerals are needed for hormone production or to maintain a normal heartbeat. Major minerals include calcium, phosphorus, potassium, sulfur, sodium, chlorine, and magnesium, while trace minerals include iron, manganese, copper, iodine, zinc, cobalt, fluoride, and selenium.
 
Major...

The minerals contained in all of the food we consume are essential for our organ systems. However, certain essential minerals, such as calcium, phosphorus, magnesium, manganese, and fluoride, largely affect bone health.
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...

The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).

When a substance such as sodium chloride is added to water, it dissolves, forming an aqueous solution. The extent of dissolution is called solubility. The process of dissolution can exist in equilibrium, just like other chemical processes. Solubility equilibria are also called precipitation equilibria because the process of solubility can be reversible. The reverse of the solubility process is called precipitation.
Solubility is important in biological and environmental processes. A notable...

A buffer can prevent a sudden drop or increase in the pH of a solution after the addition of a strong acid or base up to its buffering capacity; however, such addition of a strong acid or base does result in the slight pH change of the solution. The small pH change can be calculated by determining the resulting change in the concentration of buffer components, i.e., a weak acid and its conjugate base or vice versa. The concentrations obtained using these stoichiometric calculations can be used...