Chp 2 Assignment 2.3

1) Explain why Strontium 90 might be absorbed by your body, and why this would not be a good thing. Give an example of where this might have happened (we discussed several of these).

Stronium 90 might be absorbed into your body in lieu of calcium because they need the same amount of valence electrons to become stable. This is not a good thing because human's rely on calcium for bone structure etc… This happened in New Zealand when livestock had stronium 90 absorbed in their bodies from nuclear fallout. This caused their exported dairy products, i.e. milk, cheese, to become strontium 90 positive. When your body absorbs strontium, it can no longer absorb the calcium you need.

2) Explain why Cesium might be released from a recent accident, and how it would impact your body, using the periodic table.

Cesium was released from the daichi power plant in Japan . It is dangerous because it can take the place of potassium which is an essential element in plants and animals. When your body absorbs cesium it cannot absorb the potassium that your body needs.

3) Why might soap disable a plants' ability to draw water up to its leaves?

Capillary action can no longer occur because it relies on the cohesion of water molecules. Soap inhibits this cohesive property.

4) Explain how soap changes surface tension, and how this might be helpful in removing grease.

Soap "holds hands" with both water, and grease. This way it can wash the grease away by having it combine with water.

5) Which pairs of nucleotides bond to each other in the DNA strand?

A-T, G-C. (Adenine, thymine) (guanine, cytosine)

6) The inset on water mentioned several other physical qualities that could be important to life on this planet. Explain how specific heat and heat of vaporization enable life as we know it on our planet, and why Keck is looking for liquid water in the universe.

Specific heat is a major property of water. A high specific heat allows water to be resistant to temperature change. This also allows the atmosphere to maintain a constant temperature, allowing for life. Keck is looking for water on planets because this could be indicative of a livable planet.

7) Locate the main "sinks" for the following: carbon, phosphorus, nitrogen, oxygen, sulfur

Main Sinks

carbon: ocean

phosphorus: deep ocean sediments

nitrogen: atmosphere

oxygen: atmosphere

sulfur: underground

8) Lookup the following functional groups (wikipedia is useful here) and label each with it's charge: carbonate, nitrate, phosphate, sulphate, chloride, hydroxide, ammonium

carbonate: -2

nitrate: -1

phosphate: -3

sulphate: -2

chloride: -1

hydroxide: -1

ammonium: +1

9) Using your answers above, combine each functional group with one of these: hydrogen, calcium, chlorine, potassium, sodium

hydrogen: carbonic acid, nitric acid, phosphoric cid, sulfuric acid, sodium chloride, sodium hydroxide, ammonium chloride.

10) Which of your answers above are acids or bases?

Acids: carbonic acid, nitric, phosphoric acid, sulfuric acid.

Bases: sodium hydroxide.

11) You are now a third-world farmer (not the correct term, but the name of a simulation game) and need to ensure your crops have the proper major nutrients. What are these three nutrients, how do we refer to them in fertilizer, and what form do they often take in this fertilizer?

Phosphorus, nitrogen, potassium.

Phosphorus pentoxide, potassium oxide, and nitrogen.

12) Water is "amphoteric". What does this mean, and include some form of structure in your answer.

Amphoteric means it can act as a base as well as an acid. When combined with an acid it acts as a base (H2O + HCl → H3O+ + Cl-). When combined with a base it acts as an acid. (H2O + NH3 → NH4+ + OH-).