Lab #
Date:
Title: Types of Crystal
Problem Statement: A chemistry student was provided with three (3) unknown white crystalline
solids and was told by the teacher that they are granulated sugar, table salt, and camphor ball.
Plan and design an experiment to help the student identify each solid.
Hypothesis: crystal a is granulated sugar, crystal b is table salt and crystal c is camphor ball.
Aim: To identify three (3) unknown white crystalline solids (granulated sugar, table salt,
camphor ball) using their solubility in water and alcohol.
Apparatus/Materials: crystalline solids (A, B, C), beaker, water, ethanol, stirring rod, measuring
cylinder, electronic balance, spatula, petri dish, evaporating dish, Bunsen burner.
Procedure:
1. Measure 10g of each crystal. Place each crystal into a petri dish and label them A, B, C.
2. Measure 50 mL of water into three (3) beakers. Add each crystal to each to the beaker of
water and label them A1, B1, C1.
3. Stir the solution until the crystals have dissolved.
4. Measure 10g of each crystal. Place each crystal into a beaker and label them A2, B2, C2
5. add 50ml of ethanol to each crystals in the beaker and mix it thoroughly.
6. Record all observations.
Variables:
Controlling: 50ml of water, 50ml of ethanol, 10g of each crystals.
Manipulating: Crystal (A, B, C), water, ethanol.
Responding: Solubility of the crystal in water and ethanol.
Data to be collected:
Sample
Solubility in water
Solubility in ethanol
A
B
C
TABLE SHOWING THE SOLUBILTY OF THE CRYSTALS IN WATER AND ETHANOL
Expected Results:
Talk about what is expected
Treatment of Results:
Limitation:
Assumption: The reagents being used are pure.
Possible source of error:
Date
Title: Redox Titration
Problem Statement: You are advised to take iron tablets to improve your blood count. At the
pharmacy, there are three brands available, each containing iron in the form of iron 2
compounds. Plan and design an experiment which you can perform in your school laboratory to
determine which of the three tablets A, B, or C has the highest concentration of iron.
Hypothesis: Tablet A has the highest concentration of iron while tablet C has the lowest
concentration of iron. Tablet B has the second highest concentration of iron.
Aim: To determine which of the three tablets A, B, or C contains the highest concentration of
iron.
Apparatus/Material: burette, clamp and stand, conical flasks, beakers, petri dishes, 25cm3
pipette, pipette filler, funnel, 250cm3volumetric flask, pestle and mortar, measuring cylinder,
electronic balance
Reagents: Iron tablets of three separate brands, 0.05M of potassium permanganate(VII), 1.0 M of
sulfuric acid, distilled water
Procedure:
1.
Variables
Controlling:
Manipulating:
Responding:
Data to be Collected:
Expected Results:
Treatment of Results:
Limitation:
Assumption:
Possible source of error: