What is the standard enthalpy of the reaction:

2 NO(g) + O2(g) → 2 NO2(g)?

hi,

the answer is d, it has indefinite shape but definite volume.

hope this !

confused

confused             hewdejdnjnjsnd

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.