Write the molecular formula of the given compounds.
(i) aluminium sulphate (ii) calcium chloride
(iii) ferrous hydroxide
(iv) aluminium phospha
(v) ferric nitrate
(vi) gold chloride
(vii) silver nitrate
plz

(i) Al2(SO4)3

(ii) CaCl2

(iii) Fe(OH)2

(iv)AlPO4

(v) Fe(NO3)3

(vi) AuCl3

(vii) AgNO3

Explanation:

The numbers after the element/ion is a subscript meaning its put below the symbol

(i) Al has a charge of 3+ and SO4 has a charge of 2-

So to balance the charges 2 Al is needed to make the charge a 6+ and 3 SO4 is needed to make the charge a 6-. Once you can add the two charge values together to create 0, then you have the correct quantities

(ii) Same applies here, but Ca is 2+ and Cl is 1-, so 2 Cl- is needed to balance out the Ca

(iii) Ferrous is an ion of Iron with a 2+ charge, the other ion of Iron is Ferric which has a 3+ charge. OH has a charge of -1, so 2 OH is needed to balance out one Fe

(iv) Aluminum again has a charge of 3+ while PO4 has a charge of 3-, so they both balance out with one of each.

(v) Ferric is an ion of iron with a charge of 3+ and NO3 has a charge of 1-, so three of NO3 is needed to balance.

(vi) Gold has two charges, 1+ or 3+. However used in Gold chloride it is a 3+ and Cl is a 1-, so 3 of Cl is needed to balance one gold.

(vii) Silver has a charge of 1+ while NO3 has a charge of 1-, so they balance each other at one each.

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.