chemistry in daily life

1. WELCOME

3. CHEMISTRY IS A BIG PART OF YOUR
EVERYDAY LIFE. YOU FIND
CHEMISTRY IN DAILY LIFE IN THE
FOODS YOU EAT, THE AIR YOU
BREATHE, YOUR SOAP, YOUR
EMOTIONS AND LITERALLY EVERY
OBJECT YOU CAN SEE OR TOUCH.
HERE'S A LOOK AT SOME EVERYDAY
CHEMISTRY.

4. ELEMENTS IN THE HUMAN BODY
Most of the human body is made
up of water, H2O, with cells
consisting of 65-90% water by
weight. Therefore, it isn't surprising
that most of a human body's mass
is oxygen. Carbon, the basic unit
for organic molecules, comes in
second. 99% of the mass of the
human body is made up of just six
elements: oxygen, carbon,
hydrogen, nitrogen, calcium, and
phosphorus. You may also wish to
view the element composition of
an average human body by mass.

5. Oxygen (65%)
Carbon (18%)
Hydrogen (10%)
Nitrogen (3%)
Calcium (1.5%)
Phosphorus (1.0%)
Potassium (0.35%)
Sulfur (0.25%)
Sodium (0.15%)
Magnesium (0.05%)
Copper, Zinc, Selenium, Molybdenum, Fluorine,
Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)
Lithium, Strontium, Aluminum, Silicon, Lead,
Vanadium, Arsenic, Bromine (trace amounts)

6. WHY ICE FLOATS
A substance floats if it is less dense, or
has less mass per unit volume, than
other components in a mixture. For
example, if you toss a handful of rocks
into a bucket of water, the rocks,
which are dense compared to the
water, will sink. The water, which is
less dense than the rocks, will float.
Basically, the rocks push the water out
of the way, or displace it. For an
object to be able to float, it has to
displace a weight of fluid equal to its
own weight.

7. WHY ONION MAKE YOU CRY
Unless you've avoided cooking, you've
probably cut up an onion and
experienced the burning and tearing you
get from the vapors. When you cut an
onion, you break cells, releasing their
contents. Amino acid sulfoxides form
sulfenic acids. Enzymes that were kept
separate now are free to mix with the
sulfenic acids to produce propanethiol S-oxide,
a volatile sulfur compound that
wafts upward toward your eyes. This gas
reacts with the water in your tears to
form sulfuric acid. The sulfuric acid
burns, stimulating your eyes to release
more tears to wash the irritant away

8. HOW SOAP CLEANS
Soaps are sodium or potassium fatty acids
salts, produced from the hydrolysis of fats
in a chemical reaction called
saponification. Each soap molecule has a
long hydrocarbon chain, sometimes called
its 'tail', with a carboxylate 'head'. In
water, the sodium or potassium ions float
free, leaving a negatively-charged head.
Soap is an excellent cleanser because of
its ability to act as an emulsifying agent.
An emulsifier is capable of dispersing one
liquid into another immiscible liquid. This
means that while oil (which attracts dirt)
doesn't naturally mix with water, soap can
suspend oil/dirt in such a way that it can
be removed.

9. DOES BOTTLE WATER GO BAD
Although bottled water has an expiration
date, it doesn't actually go bad. Why is
there an expiration date on a product that
doesn't go bad? This is because New Jersey
requires all food and beverages, including
water, to carry an expiration date on its
packaging. It doesn't matter if you don't
live in New Jersey... your water may carry
an expiration date anyway to make it easier
to standardize packaging. Some bottled
water only carries its bottling date or a
'best by' date. These dates are helpful
because the flavor of the water will change
over time as it absorbs chemicals from its
packaging. The flavor will not necessarily
be bad, but it may be noticeable.

10. FRUIT THAT RUIN JELL-O
The fruits that ruin Jell-O contain enyzmes
called proteases which break the chemical
bonds that try to form between chains of
protein as Jell-O or other gelatin tries to
gel.pineapple - bromelain
kiwi - actinidin
figs - ficain
papaya - papain
pawpaw - papain
mango
guava
ginger root

11. LAUNDRY DETERGENT IN THE
DISHWASHER
Modern laundry detergents tend not to
produce mountains of bubbles, but there are
other good reasons to not substitute laundry
detergent for dishwashing detergent. One
reason is that you likely void the warranty on
the appliance if you use a product not made
for dishwashers. You may be exposing yourself
to toxins, too. The detergent itself may be the
same from one product to the other, but
laundry detergents may contain brighteners,
fragrances, stain removers, and anti-soiling
chemicals that you don't really need volatilized
by the heat of your dishwasher so that you
breathe them. The ingredients in laundry
detergent might not rinse completely from
your dishes.

12. BAKING POWDER VS BAKING SODA
Both baking soda and baking
powder are leavening agents,
which means they are added to
baked goods before cooking to
produce carbon dioxide and cause
them to 'rise'. Baking powder
contains baking soda, but the two
substances are used under
different conditions.

13. HOW SUNSCREEN WORKS
Sunscreen combines organic
and inorganic chemicals to
filter the light from the sun so
that less of it reaches the
deeper layers of your skin.
Like a screen door, some light
penetrates, but not as much
as if the door wasn't present.
Sunblock, on the other hand,
reflects or scatters the light
away so that it doesn't reach
the skin at all.