Question

We use rice, dhal, sugar and other grosseriees with proper quantity/ mass. Likewise

each atom has mass. With the help of atomic masses we can calculate the molecular

masses. Calculate the molecular masses for the following:(use A4 Sheet).

CH3COOH, N2O3,Na2CO3, H3PO4,PH3,KOH,AlCl3, PbNO3, ZnCl2, MgO​

Answer 1

Answer:

By the end of this section, you will be able to:

Symbolize the composition of molecules using molecular formulas and empirical formulas

Represent the bonding arrangement of atoms within molecules using structural formulas

Define the amount unit mole and the related quantity Avogadro's number

Explain the relation between mass, moles, and numbers of atoms or molecules and perform calculations deriving these quantities from one another

Molecular and Empirical Formulas

A molecular formula is a representation of a molecule that uses chemical symbols to indicate the types of atoms followed by subscripts to show the number of atoms of each type in the molecule. (A subscript is used only when more than one atom of a given type is present.) Molecular formulas are also used as abbreviations for the names of compounds.

The structural formula for a compound gives the same information as its molecular formula (the types and numbers of atoms in the molecule) but also shows how the atoms are connected in the molecule. The structural formula for methane contains symbols for one C atom and four H atoms, indicating the number of atoms in the molecule (Figure 2.16). The lines represent bonds that hold the atoms together. (A chemical bond is an attraction between atoms or ions that holds them together in a molecule or a crystal.) We will discuss chemical bonds and see how to predict the arrangement of atoms in a molecule later. For now, simply know that the lines are an indication of how the atoms are connected in a molecule. A ball-and-stick model shows the geometric arrangement of the atoms with atomic sizes not to scale, and a space-filling model shows the relative sizes of the atoms.