Solve all using two methods each 4. Calculate the mass of anhydrous Na2CO3 in 25.0 cm3 of the saturated solution at 30oC, if its solution at this temperature is 1.80 moldm-3 [Na = 23, C = 12, O = 16]

5.
What volume of a saturated solution of X at 0oC would yield 10.0 g of the dry salt, if the solubility of Y at 0oC is 5.0 moldm-3? [X=160]

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

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.