Elements in Living Things Biotic Matter Bio = life

What means something is alive? Life = Grows during its lifetime Reproduces – makes offspring Responds to a stimulus Uses energy to grow and repair

C Carbon H Hydrogen N Nitrogen O Oxygen Four elements are usually found in living systems.

C 6 H 12 O 6 sugar CO 2 H2OH2O NN

C Carbon H Hydrogen N Nitrogen O Oxygen Remember “CHNO” (“ sha know” )

Elements of the Ocean As you know, oceans are made of water…actually ocean water is salt water. Salt water is the key to understanding what elements are most common in our oceans. The four most common elements found in the ocean are not found by themselves. Like Earth’s crust, our oceans are dominated by compounds. Two compounds make up the vast majority of our oceans. Knowing the compounds making up salt water should give you a big clue about the four most common elements in oceans.

Elements of the Ocean cont. Water is, of course, a compound with the chemical formula (H 2 O). Salt is the common name for the compound Sodium Chloride (NaCl).

Percentage of Elements in the Ocean ElementPercentage % Oxygen (O) Hydrogen (H) Chlorine (Cl) 1.94 Sodium (Na) 1.08 Magnesium (Mg).13

Elements in the Ocean

Elements found in the Earth’s Atmosphere

AAAAtmosphere: the layer of gases surrounding Earth. TTTThe atmosphere is held in place by the force (pull) of Earth’s gravity. OOOOur atmosphere reflects a great deal of the Sun’s radiant energy, protecting Earth from harmful levels of radiation… but what is it made up of?

TTTThe atmosphere is made up largely of two elements. NNNNitrogen makes up 78% of the atmosphere. Oxygen is just 21% of our atmosphere. WWWWhen asked if the atmosphere is made mostly of Oxygen…the correct reply is NO! Get it? NO = Nitrogen (N) first at 78% Oxygen (O) second at 21%

Trace Elements SSSSmall amounts of other elements are also present in our air. The final 1 % of the atmosphere is filled with several other gases including two very important compounds…water vapor (H2O) and Carbon Dioxide (CO2) compound element Wait!! What is this word? Is a compound the same as an element!!

two or more elements H 2 O more than one capital means multiple elements pure substance H Only one capital letter means one element This element (hydrogen H) is a gas that is very explosive!! Elements Compounds Elements Compounds

EEEElements found in the atmosphere are very important to all living organisms. NNNNitrogen (N) is an important element supporting plant life. In fact, Nitrogen (N) is found in fertilizers. BBBBoth plants and animals alike must have water (H2O) to live. Importance of Atmosphere Elements

Greenhouse Gas IIIIn addition to the gas Nitrogen, plants also need the compound Carbon Dioxide (CO2), which is also a gas. CCCCarbon Dioxide is also known as a greenhouse gas. GGGGases like this can contribute to Global Warming – the heating of our planet due to gases trapping heat.

So the breakdown of elements in our atmosphere is…

Elements in the Earth’s Crust

Elements of Earth’s Crust Notetaking – remember if it’s white, you write Elements of Earth’s Crust Notetaking – remember if it’s white, you write Crust: the outermost layer of our planet. The crust is broken into pieces called plates. All of Earth’s features (mountains, canyons, rivers, valleys, oceans, volcanoes, etc.) are located in the crust. At least 90 elements have been found in the crust. However, just 5 of these elements make up most of the crust.

Elements are not usually found as pure samples in the crust. Pure elements, like Gold (Au) and Silver (Ag), are extremely rare. They are just a very, very, tiny amount of the total mass of all elements in Earth’s crust. (This is why they are valuable…they are extremely rare!) Elements can combine with each other during a chemical reaction and form a different substance with different properties.

Compounds: when elements combine chemically into a substance very different from the original elements. In fact, Earth’s surface is made mostly of compounds. For example, rocks and minerals are almost always compounds. Elements found in our crust are most often a part of compounds.

Look at the table below listing the most common compounds found in the crust. Do you see something in common in these formulas? Compounds in Earth’s Crust Compound Formula Abundance percent by mass Silicon dioxide SiO % Magnesium oxideMgO35.07% Ferrous oxideFeO8.97% Aluminum oxideAl2O36.99% Calcium oxideCaO4.37% All the most plentiful compounds include the element Oxygen (O).

Oxygen (O) is the most common element in our crust. Remember – O is an element and it combines with other elements to make compounds. Silicon (Si) is the second most common. These two make up about 75% of the elements in the crust. Next most common are Aluminum (Al), Iron (Fe), and Calcium (Ca).

On your graph paper, draw the graph above. Be sure to use TAILS!! When you label the x-axis, use the data table to know which element each bar represents. On your graph paper, draw the graph above. Be sure to use TAILS!! When you label the x-axis, use the data table to know which element each bar represents. You will need a half sheet of graph paper. Crust Elements % by mass Oxygen (O)47% Silicon (Si)28% Aluminum (Al)8% Iron (Fe)5% Calcium (Ca)4%