Distilled or Mineral…Does

It Matter?

Crystal growing

Introduction

My name is Matthew Marchetti and I am a 6th grader. I am homeschooled and I only do Science in FLVS. (Physics 1) I am especially interested in Geology and collecting things like rock samples and growing crystals.

Purpose

My purpose is to test if a crystal will grow bigger in distilled water, spring water, mineral water, or

purified water.

Research

I looked up (http://www.sciencefair-projects.org/chemistry-projects/growing-a-crystal.html) to get my overall procedure. (We did it

a bit differently.)

Hypothesis

If crystals are grown in mineral water, then they will grow bigger in the same amount of time, than they will in distilled water, spring

water, or purified water.

Materials

Alum Distilled water Spring waterMineral water Purified water4 glass containersMicrowaveStirring stickScale in 10th of grams

Procedure

1.Pour ½ a cup of mineral water into a glass.2.Heat the water in the glass in the microwave for one minute.3.Pour in 2 ½ tbsp. of alum and stir for one minute with the stir stick.4.Set the glass in a place where it can not be disturbed.5.Repeat steps 1 through 4 with the other water samples.

6.Place a paper over the 4 glasses.7.Wait 48 hours.8.Pull out and examine.9.Weigh the crystals you have obtained.10.Write down your results.

Procedure

1. When we mixed the alum into the water samples, all the alum was dissolved, and the water looked murky.

2. It only took twelve hours for the crystals to form. The crystal was shaped like a hexagon, as you can see in the picture at the top left corner. The biggest crystal was about 1.5 inches across. As you see, its shape is irregular so we could not measure it precisely with a ruler.

Discussion(Observations)

3. I weighed the crystals in the Biology Lab at Valencia College. We thought it would be better to weigh all the crystals in the container rather than just the “bigger” crystals.

Discussion(Observations 2)

Discussion(Errors)

In our experiment we had some errors. 1. We used a different brand of alum for the purified water for the first experiment. Maybe that is why the purified water had the smallest crystals for the first experiment.

2. I know there are some unknown variables in my experiment that I did not notice. In the second experiment we had to redo the mineral water because it did not have enough alum. 3. Also, we thought that two tsp. equal one tbsp.. In addition, the equipment in Valencia College introduced errors.

Discussion(Errors 2)

Data

Type of water Weight for Exp. 1 Weight for Exp. 2

Mineral 19g 25.5g

Distilled 18.6g 24.7g

Spring 20.3g 26.1g

Purified 10.1g 24.7g

Analysis

spring purified distilled mineral0

5

10

15

20

25

30Exp.1

Exp. 2

Weight of Crystals in Grams

gram

s

Experiment 1 Crystals

Experiment 2 Crystals

Conclusion

My hypothesis was incorrect. Fortunately, I learned that spring water grows crystals with more weight than distilled water, purified

water, and mineral water. The reason I picked mineral water is because I thought the minerals would collect on the crystal making

it bigger. Unfortunately, we could not find out why spring water came out on top. This could be a coincidence but we are not sure.

I am very thankful to my dad for helping me with this experiment. Whether I win a prize from this

project or not, I will still walk away with a reward: the time I spent with

my dad.