Lab Report
Physical Properties of Two Types of Solids
SCH3U0
Maggie Liu
Abstract
The purpose of this lab is to study some of the physical properties of two types of solids – ionic and molecular. The samples used are sodium chloride (ionic) and camphor (molecular). The physical properties studied are odour, hardness, melting point, solubility in water and solubility in 2-propanol. It is observed that some of the physical properties of sodium chloride are no odours, hard, a high melting point, soluble in water and insoluble in 2-propanol; some of the physical properties of camphor are a strong odour, soft, a low melting point, insoluble in water and soluble in 2-propanol. A few conclusions can be drawn from these observations. The particles in ionic solids are held tightly by the force of attraction between ions with opposite charge, because of this strong force of attraction of positive and negative, ionic solids tend to have no odours, a high melting point and they are hard. The particles in molecular solids are held by the van der Waals force of attraction, because of this relatively weak force of attraction, molecular solids have a strong odour, a low melting point and they are soft. Sodium chloride dissolving in only water (not in 2-propanol) and camphor dissolving in only 2-propanol (not in water) have proved that polar solids are soluble in polar liquids only, and non-polar solids are soluble in non-polar liquids only.
Introduction Ionic solids form as a result of the chemical reaction between metals and non-metals. Atoms that become positively charged by losing electrons are called cation; atoms that become negatively charge by gaining electrons are called anion. During the formation of ionic solids, a few electrons from the metals are transferred completely to the non-metals. The attraction between ions of opposite charge is what virtually holds the particles in ionic solids together. The other type of solids is molecular