Answer:
La metrología es la ciencia que se ocupa de las mediciones, unidades de medida y de los equipos utilizados para efectuarlas, así como de su verificación y calibración periódica.
Answer:
Group 17 elements:
Flourine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (As).
Period 2 elements:
Lithium (Li), Beryllium (Be), Boron (B), carbon (C), Nitrogen (N), Oxygen (O), flourine (F), And Neon.
There are 18 numbered groups in the periodic table, and the f-block columns (between groups 3 and 4) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e., the same core charge), as most chemical properties are dominated by the orbital location of the outermost electron. There are three systems of group numbering. The modern numbering group 1 to group 18 is recommended by the International Union of Pure and Applied Chemistry (IUPAC). It replaces two older naming schemes that were mutually confusing. Also, groups may be identified by their topmost element or have a specific name. For example, group 16 is variously described as the oxygen group and as the chalcogens.
Answer:
A. the iron atoms are gaining kinetic energy
Explanation:
when the iron melted and solidifies it loses potential energy and changes to kinetic energy
An energy diagram of a chemical reactions illustrates the changes of energy as the chemical reactions advances.
At first, the energy in the diagram is the energy of the reactants.
As the reaction goes forward, the reactants start to react forming a transition compound, with a maximum energy level on the graph. This is the hill. So the hill represents the Activation Energy.
After that, the energy starts to decrease and at the end you have the energy of the products, which may be higher or lower than the initial energy of the reactants, depending upon whether the reaction is exothermic or endothermic.
For exothermic reactions the energy level of the products is lower than the energy level of the reactants, while for endothermic reactions the energy level of the products is higher than the energy level of the reactants.
