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Natural sciences

Reactions that occur between different kinds of matter: acids and bases

Educator section

Memorandum

It is very important that you ensure beforehand that the substances collected by the groups are safe for tasting.

Black tea as indicator.

ACIDS NEUTRAL ALKALIS
Salt and vinegar Vanilla essence (sweet) Cocoa powder
Spices Instant soup (salty) Green pepper
Turmeric Apple vinegar Bicarbonate of soda
Lemon juice Chocolate

Leaner section

Content

Warning

  • All people have senses that enable them to observe different aspects of the environment. The tongue is the sense organ that makes it possible to observe the taste of substances. Never taste any substance if you are not altogether sure that it is harmless! People often store substances in containers that do not have the necessary labels. We quite frequently have dangerous substances in our homes, e.g. battery acid, ammonia and pool acid. Remember that it is unwise to taste anything that cannot be identified as harmless.

Activity: to identify acids and bases in and around the home [lo 1.2, lo 2.2]

Most acids have a sour taste, while most bases are bitter. The rear area of the tongue identifies these tastes. The foremost part of the tongue records the taste of substances that are sweet or salty. Substances such as these are neither acids nor bases, but are neutral.

Check through your mother's kitchen cupboards and bring some of the following to school with you:

Toothpaste

  • Ask your mother to help you ensure that you do not bring dangerous substances like ammonia or bleaching agents to school with you.
  • Form groups and draw up lists of the substances that you have in your group.
  • Get your educator's help in ensuring that all the substances are safe to taste.

Complete the following table by tasting all the substances and recording your observations.

ACIDSThese substances have a sour taste NEUTRALThese substances taste neither sour nor bitter BASESThese substances have a bitter taste
______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________
______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________
______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________
______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________
______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________ ______________________________________________________________________________________________________________

(15)

Compare your personal experience with the experiences of the other members of the group. Classify the substances in your group according to their taste. Compare your notes with those of the other groups.

  • Did everyone agree about the tastes of all the substances? __________________
  • If everyone did not agree, indicate where the differences occurred?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

Assessment

Learning Outcome 1: The learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts.

Assessment Standard 1.2: We know this when the learner conducts investigations and collects data: organises and uses apparatus/equipment or sources to gain and record information.

Learning Outcome 2: The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard 2.2: We know this when the learner categorises information.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11077/1.1
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