A. Characteristics
You would use this key and it will say something like go to 12 of it has long wings or go to 11 if it has no wings.
Answer:
○Two electrons in the outer shell and a full outer electron s shell
○Low electron affinities
○Low electronegativities
○Relatively low densities
○Relatively low melting points and boiling points, as far as metals are concerned
○Typically malleable and ductile. Relatively soft and strong.
The elements readily form divalent cations (such as Mg2+and Ca2+).
The alkaline earth metals are very reactive, although less so than the alkali metals. Because of their high reactivity, the alkaline earths are not found free in nature. However, all of these elements do occur naturally. They are common in a wide variety of compounds and minerals.
These elements are shiny and silver-white as pure metals, although they usually appear dull because they react with air to form surface oxide layers.
All the alkaline earths, except for beryllium, form corrosive alkaline hydroxides.
All of the alkaline earths react with halogens to form halides. The halides are ionic crystals, except for beryllium chloride, which is a covalent compound.
Answer:
The conservation of endangered species is important for humans as well. A well-balanced ecosystem purifies the environment, giving us clean air to breathe, a healthy water system to support diverse marine life, and arable land for agricultural production.
Explanation:
The health of an ecosystem is maintained by its plants and animals. When species become endangered, it is a sign of an ecosystem's imbalance. This balance is difficult to maintain: the loss of one species often triggers the loss of others. ... By saving endangered species, we are ultimately saving ourselves.
A cytotoxic T cell recognizes and destroys cells infected by a virus. They are also responsible for killing cancer cells too.
The answer is b because there are cracks in the ocean that are caused by two plates crashing
