Relative Density Essay

Abstract

The experiment about relative density is composed of three different activities. The first activity is about the Displacement Method for alloy, the second activity is about getting the density of a bone and the third activity is about Regular versus Diet Soft Drinks.

1. Introduction

Relative density is the ratio of the density (mass per unit volume) of a substance to the density of a given reference material. The theory or the principle that we used for the experiment is the Archimides’ Principle which states that any fluid a buoyant force to an object that is partially or completely immersed in it; the magnitude of the buoyant force equals the weight of the fluid that the object displaces.

In the experiment we used different formulas. For activity 1 (g) mass of the substance which is Aluminum, (cc) initial level of water, (g/cc) for the experimental value, magnitude of buoyant force [pic]= Wfluid which is weight of displaced fluid. For activity 2 we used formulas for getting the relative density of the bone.

For experiment 3 we used formulas like

2. Theory

Activity 1: Displacement Method for Alloy

The Aluminum bar was weighed and its mass was recorded. Some water was placed into a graduated cylinder and the initial water level was recorded. The Aluminum bar was placed inside the cylinder and the new water level was recorded. The volume of the Aluminum bar was computed by subtracting the initial water level from the resulting water level. The density of the Aluminum bar was computed by dividing its mass by its volume. The calculated density was compared to the standard density (2.7 g/cc) and the % error was taken.

Activity 2: Density of a Bone

A piece of bone was weighed in air and in water, each reading was recorded as the “weight of the bone in air” and “weight of the bone in water” The Relative Density of the bone was then computed by using the formula given. The density of the bone was then computed by multiplying the Relative density of the bone to the density of the water. The status of the bone was identified by referring to the WHO ‘s definition of the diseases a bone can have relative to its own density.

Activity 3: Regular versus Diet Soft Drinks

The weight of an empty pycnometer, the pycnometer filled with water, pycnometer filled with regular coke, pycnometer filled with coke light, and pycnometer filled with coke zero. The relative density of regular coke, coke light, ad coke zero was computed by using the formulas given.

4. Results and Discussion

Table 1 show the results from activity 1, table 2 for activity 2 in activity the finding is that the bone has osteopenia it is or low bone mass because the density of the bone is within 1.0 to 2.5 and table 3 for activity 3.