Which elements are metals? check all that apply. rhenium (re) boron (b) lithium (li) krypton (kr) phosphorus (p) mercury (hg)?

ANSWER

Lithium, rhenium , mercury , are metals out of given five elements.

As lithium is a alkali metal , rhenium and mercury both are transition metals.

based on the electronic configurations of the metals , they have valence electrons present in their valence shell  which are easily available for donation so that they can attain stable electronic configuration and thus they are considered as metals.

boron is a non metal which is the member of group 13 of the periodic table.

krypton is a noble gas which is a member of group 18 of the periodic table.

phosphorus is a non metal member of group 17 of the periodic table.

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.