Answer:
D. These elements have properties of both metals and nonmetals.
Explanation:
It can be concluded that the elements have properties of both metals and non-metals.
The elements that borders the ones described are both metals and non-metals. Most of these elements can be classified as metalloids.
On the periodic table, the elements around this region have properties of both metals and non-metals at certain temperature and pressure conditions.
Answer: B. Rusting of the metal is a chemical change.
Explanation: Rusting is considered a chemical change since it involves a change in the composition of iron through oxidation. Since there is a presence of oxygen and moisture it weakens the bonds of iron molecules to react and form iron oxide another substance in the chemical process.
One electron is shared between ethane, H3-C-C-H3
Answer:
- <u><em>Option C) Fr (francium)</em></u>
Explanation:
<em>Fluorine (F) </em>is not a metal; thus, the last option is discarded quickly.
The<em> most reactive metals</em> are the alkali metals, group 1 of the periodic table, because they have just one valence electron, which they can release more easily than other metals which have more valence electrons.
<em>Lithium(Li)</em> and <em>francium (Fr)</em> are alkali metals, while <em>aluminum (Al)</em> belongs to group 13, which means that it has 3 valence electrons.
Thus, aluminum is out of race too.
Lithium is in the second period (row 2 of the periodic table) while francium is in the last period (row 7).
The reactivity of metals in a group increases from top to bottom, because the valence electrons are shielded by many electrons (which are in the orbitals of less energy and closer to the nucleus of the atom), meaning that the valence eletrons can be released more easily.
Hence, the most reactive metal from the list is Fr (francium), option C).