Wednesday, March 18, 2020

Key Deer Essays - Deer, Mammals Of New Zealand, White-tailed Deer

Key Deer Essays - Deer, Mammals Of New Zealand, White-tailed Deer Key Deer The Key Deer is a small species (in population and in stature) of deer that lives in the Florida Keys. It is in the same family as the Virginia white tailed deer. The Key Deer is about 26 inches tall and weigh an average of about 55 pounds. The males have antlers, and the antlers grow in cycles. They drop their antlers at the beginning of spring, and they grow back by June. The deer feed on indigenous plants including the red mangrove, the black mangrove, and the white mangrove. The Key Deer can drink water with some salt in it, but needs fresh water to survive. Although it seems awkward, the Key Deer is a fairly good swimmer, and at times will swim from key to key. The Key Deer are endangered for two main reasons, the first and most detrimental is the loss of habitat. The Everglades has been cleared away for highways, and other commercial developments, and it has caused a huge drop in the population of Key Deer, among other animals. Another big reason why Key Deer have been disappearing are the highways in southern Florida. You have heard the expression like a deer in headlights, and it is used because when deer see headlights, it freezes. This, although it makes for a good simile, causes a lot of road kill accidents with Key Deer. The National Key Deer Refuge was opened to breed Key Deer, and since its opening, the population has increased by almost %600!!! Also, Ms. Riskin, please make sure that you do not feed any Key Deer, because it causes them to be comfortable around humans, which sounds nice, but it is part of the reason that they hang around near the highway. So, that just about sums it up; thanks for not feeding Key Deer, and keep your foot on those breaks. Bibliography Key Deer February, 2000 shadow.net/grgreen/glades/deer.html Kirkpatrick, Charles M. Deer The World Book Encyclopedia. Volume D, 1986 R., Austin. Key Deer February, 2000 miamisci.org/ecolinks/everglades/keydeerinfo.html

Monday, March 2, 2020

Avogadros Number - Example Chemistry Problem

Avogadros Number Chemistry Problem Avogadros number is used in chemistry when you need to work with very large numbers. Its the basis for the mole unit of measurement, which provides an easy way to convert between moles, mass, and the number of molecules. For example, you can use the number to find the number of water molecules in a single snowflake. (Hint: Its an enormous number!) Avogadros Number Example Problem - Number of Molecules in a Given Mass Question: How many H2O molecules are there in a snowflake weighing 1 mg? Solution: Step 1 - Determine the mass of 1 mole of H2O Snowflakes are made of water, or H2O. To obtain the mass of 1 mole of water, look up the atomic masses for hydrogen and oxygen from the Periodic Table. There are two hydrogen atoms and one oxygen for every H2O molecule, so the mass of H2O is: mass of H2O 2 (mass of H) mass of Omass of H2O 2 ( 1.01 g ) 16.00 gmass of H2O 2.02 g 16.00 gmass of H2O 18.02 g Step 2 - Determine the number of H2O molecules in one gram of water One mole of H2O is 6.022 x 1023 molecules of H2O (Avogadros number). This relation is then used to convert a number of H2O molecules to grams by the ratio: mass of X molecules of H2O / X molecules mass of a mole of H20 molecules / 6.022 x 1023 molecules Solve for X molecules of H2O X molecules of H2O ( 6.022 x 1023 H2O molecules ) / ( mass of a mole H2O  · mass of X molecules of H2O Enter the values for the question:X molecules of H2O ( 6.022 x 1023 H2O molecules ) / ( 18.02g  · 1 g )X molecules of H2O 3.35 x 1022 molecules/gram There are 3.35 x 1022 H2O molecules in 1 g of H2O. Our snowflake weighs 1 mg and 1 g 1000 mg. X molecules of H2O 3.35 x 1022 molecules/gram  · (1 g /1000 mg )X molecules of H2O 3.35 x 1019 molecules/mg Answer There are 3.35 x 1019 H2O molecules in a 1 mg snowflake. Avogadros Number Problem Key Takeaways Avogadros number is 6.02 x 1023. It is the number of particles in a mole.You can use Avogadros number to convert between mass and the number of molecules of any pure substance.If you are given the mass of a sample (such as a snowflake), convert the mass to moles, and then use Avogadros number to convert from moles to molecules.