# 0.12 Amphoteric aluminum

 Page 1 / 2

Properties of Aluminum and Its Compounds

## Objectives

• To prepare common alum, $\text{KAl}\left({\text{SO}}_{4}{\right)}_{2}\text{.}\text{12}{H}_{2}O$ , from a discarded aluminum beverage can.
• To perform qualitative analysis on alum.
• To investigate the acid-base behavior of aluminum compounds.

You grade will be determined based on the following:

        Pre-lab (10%)

        Lab Report Form (80%)

        TA evaluation of lab procedure (10%)

Before coming to lab…..

        Print out the lab instructions and report form

• Complete the pre-lab, due at the beginning of the lab. See page 616 in Brown, LeMay and Bursten for the definition of amphoteric behavior.

## Introduction

Aluminum is the most abundant metal in the earth's surface (7.5% by mass). The abundance of aluminum, coupled with its attractive combination of physical and chemical properties, accounts for the fact that it is one of the principal industrial raw materials used by industrialized societies. Production of aluminum from raw materials is an energy intensive process.

Since the metal is not consumed rapidly by corrosion, the amount of scrap aluminum grows rapidly while the available supply of raw materials for the manufacture of aluminum decreases. The average predicted longevity of an aluminum can along the roadside is 100 years.

Environmental problems thus created are typical of those of several different metals. One obvious solution to the problem is to recycle the used fabricated aluminum into other useful metallic objects or into aluminum compounds. Aluminum metal can be recovered from scrap by melting the metal and separating it from solids and volatile impurities. This process uses a large amount of energy. The energy requirement to prepare an aluminum can from recycling is only 5% of the energy required to produce the can from bauxite ore.

This experiment illustrates a chemical recovery process in which waste aluminum is converted chemically into an aluminum compound, hydrated potassium aluminum sulfate, $\text{KAl}\left({\text{SO}}_{4}{\right)}_{2}\text{.}\text{12}{H}_{2}O$ , or common alum. Although alum is an important industrial compound, the method of preparation in this experiment is not the way alum is obtained for use in industry. Nevertheless, this experiment will illustrate an interesting example of the reduction of environmental waste. "Alum" is a generic term that describes hydrated double salts of certain metals having the generalized formula, $\left[\text{MM}\text{'}\left({\text{SO}}_{4}{\right)}_{2}\text{.}\text{12}{H}_{2}O\right]$ , in which M (univalent) is commonly ${\text{Na}}^{+}$ , ${K}^{+}$ , ${\text{NH}}_{{4}^{+}}$ , or ${\text{Rb}}^{+}$ and M' (trivalent) is commonly ${\text{Al}}^{3+}$ , ${\text{Ga}}^{3+}$ , ${V}^{3+}$ , ${\text{Cr}}^{3+}$ , ${\text{Mn}}^{3+}$ , ${\text{Fe}}^{3+}$ , or ${\text{Co}}^{3+}$ . True alums crystallize in well-defined octahedral shapes and many are beautifully colored, particularly those containing d-block transition metals. The ancient Egyptians, Greeks and Romans used alum as a mordant in dyeing cloth. A mordant contains metal ions that bind dyes to the fabric. Presently alum is used to harden photographic film, to prepare pickles, as a mordant, and for other purposes.

## Experimental procedure

Wear safety goggles. Wear gloves when using concentrated acid and base.

where we get a research paper on Nano chemistry....?
what are the products of Nano chemistry?
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
Got questions? Join the online conversation and get instant answers!