PRE – LABORATORY
Experiment Number: 3
Name of Experiment: Elements, Compounds and Mixtures
REPORT
Date of Experiment: February 2, 2024
Course Code: CHE10 Chemistry for engineers
Degree & Section: BS Civil Engineering 1C
Group Number: 7 Introduction (Important Concepts) (30%)
Group Members: Cabuyaon, Chloe Shazny G. Objective (5%)
De Vera, Jerilou D. Equipment, Materials and Reagents (5%)
Pascua, Vhikansel Andrei V. Process Flow Diagram (50%)
Ragusante, Camille C. Report Quality and Format (10%)
Soriano, Romel Paolo M. (Leader) Total (30 points)
I. Introduction
The world around us is brimming with diverse materials, each possessing unique properties and compositions. From the air
you breathe to the food you eat, everything is composed of matter, which can be broadly classified into two categories: pure
substances and mixtures. Understanding how these materials are built plays a fundamental role in various fields, from chemistry
and physics to engineering and medicine.
Firstly, we encounter pure substances, materials exhibiting a uniform composition and distinct set of properties. These can
be further divided into two categories: elements and compounds. Elements, the building blocks of matter, consist of atoms of a
single type. Familiar examples include gold, iron, and oxygen. In contrast, compounds are formed by the chemical combination of
atoms from different elements in a fixed ratio. Water (H2O) and salt (NaCl) are common examples. Both elements and
compounds have distinct properties that remain constant throughout, regardless of their size or shape. Notably, pure substances
cannot be further broken down by physical means.
On the other hand, mixtures represent a physical blend of two or more distinct pure substances, each retaining its original
chemical identity. Unlike pure substances, mixtures exhibit variable compositions and display properties that are a culmination of
their individual components. Examples include sand (a mixture of various minerals) and air (a mixture of gases like nitrogen and
oxygen). Interestingly, the components of mixtures can be physically separated using a variety of techniques tailored to their
unique properties.
Decantation offers a simple method for separating a liquid from a dense insoluble solid, utilizing gravity to settle the solid
and then pouring off the liquid. Filtration employs a porous material, like filter paper, to capture solids while allowing liquids to
pass through, ideal for separating finer particles. When a soluble component needs to be isolated from an insoluble one,
extraction comes into play. This technique involves dissolving the desired component in a suitable solvent, followed by separation
from the undissolved material. Finally, sublimation offers a unique approach for separating volatile solids, transforming them
directly into gas without passing through a liquid state.
Understanding the distinction between pure substances and mixtures forms the bedrock of various scientific inquiries. By
investigating the composition of materials, scientists can unlock their properties, design new materials with desired attributes, and
develop applications that impact diverse fields. From purifying drinking water to formulating life-saving drugs, the knowledge of
pure substances and mixtures empowers us to navigate the fascinating world of matter and its endless possibilities.
II. Objectives
In this experiment, the primary focus is on carefully distinguishing between elements and compounds, while highlighting the
nuanced differences between pure substances and mixtures. The investigation goes a step further by quantifying the specific
percentage of individual components within a given mixture. Moreover, the experiment delves into the careful process of
determining the percentage recovery, offering valuable insights into the efficiency of substance separation methods and the
overall composition of the tested mixture. This approach aims to deepen the understanding of the complexities involved in
characterizing and isolating substances in a laboratory setting, providing students with a comprehensive exploration of chemical
concepts.
III. Equipment, Materials and Reagents
Equipment Materials Reagents
25-mL Graduated Spatula Match Magnesium ribbon
Cylinder
100-mL Beakers Test Tube Holder Ammonium chloride
(2)
Clamp Stirring Rod Sodium chloride
Evaporating Weighing Balance Sand
Dishes (2)
Gas Burner Thermometer
Iron Stand Tongs
Iron Ring Watch Glass
Wire Gauze
Table 1 summarizes the equipment, materials and reagent chemicals needed for the experiment.
IV. Process Flow Diagram
Prepare all the necessary
Formation of equipment, materials, and reagents. Separation of 3 solids:
Magnesium oxide NaCl, NH4Cl, & Sand
Describe the properties of Weigh sample of a mixture
the Magnesium Ribbon containing NaCl, NH4Cl &
sand in pre-weighed
evaporating dish
Scrape the Magnesium strip
with a blunt knife of with the Heat the evaporating dish
edge of a steel spatula until it containing the sample and
turns into a metallic luster. stir it with stirring rod every 2
Observe minutes until one component
gets evaporated and then
condenses to form solid form
Light up the Bunsen burner
to ignite the magnesium
ribbon Let the evaporating dish with
the content to cool to room
temperature and weigh the
Use a test tube holder to evaporating dish with the
hold the magnesium ribbon mixture. Record the data and
and light the end on the determine what separation
Bunsen burner. Describe techniques is applied.
what takes place Add 25mL of water to the
remaining mixture, stir the
contents gently
Carefully transfer the liquid to
the second pre-weighed
evaporating dish, being
careful not to spill any solids
into the second evaporating
dish.
Carefully heat the
evaporating dish containing Heat the evaporating dish
Add 10mL of water to the containing the wet sand over
the solution to evaporate the solids in the first evaporation
water. When half of the water low heat until the sand dries
dish. Repeat the extraction and let it cool to room
in the solution has with another 10mL of water
evaporated, cover the temperature. Record the
evaporating dish with a pre- mass.
weighed watch glass. When
the solid has dried
completely, let the
evaporating dish cool to
room temperature. Weigh the
evaporating dish, watch
glass and its content tabulate Identify the property of each
results of the component and
calculate the percent of
component of each
substance in the mixture and
the percent recovery
