Oque é número atômico e porque ele é importante para o quimico

Átomos normais têm o mesmo número de elétrons que prótons. O número de elétrons é o que faz com que cada elemento se comporte de certa maneira nas reações químicas. Portanto, o número atômico, que é o número de prótons e, portanto, dos elétrons, é o que torna um elemento diferente do outro. Os átomos são neutros na carga elétrica porque possuem o mesmo número de elétrons negativos que os prótons positivos. Portanto, o número atômico de um átomo também informa quantos elétrons o átomo possui. Isso, por sua vez, determina muitas das propriedades do átomo.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

the term hydride is commonly named after binary compounds that hydrogen forms with other elements of the periodic table. hydride compounds in general form with almost any element, except a few noble gases. the trends and properties vary according to the type of intermolecular force that bonds the elements together, the temperature, its molecular masses, and other components. hydrides are classified into three major groups, depending on what elements the hydrogen bonds to. the three major groups are covalent, ionic, and metallic hydrides. formally, hydride is known as the negative ion of a hydrogen, h-, also called a hydride ion. because of this negative charge, hydrides have reducing, or basic properties. its special characteristics will be further discussed.

explanation: