School/ Campus Teacher 7 th Grade- CI 4 L 4 Name:____________________________________ Date:____________________ DN: Law of Conservation of Mass Review Team:___________________ Directions: Answer the following questions. 1. What is the law of conservation of mass? ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ __________________ ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ __________________ 2. Does this reaction follow the law of conservation of mass? Explain using specific vocabulary from the diagram. Reactant Products ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ __________________
Rank the following reservoirs from containing the most amount of water (1) to the least amount of
water (7).
______Atmosphere
______Glaciers
______Groundwater
______Lakes
______Oceans
______Rivers
______Other reservoirs
STOP
School/ CampusTeacher
7th Grade- CI 4 L 4
Prompt: Imagine that all the water on Earth could fit into a space the size of your science classroom. How much space would all the glaciers take up? What about all the water in lakes? Use evidence from today’s investigation and text to support your thinking. Hint—compare these amounts to objects you see around you, using a ratio or scale.
Procedure:
Use 1000 mL of water to represent all the water on Earth. This will help you visualize how reservoirs compare. Follow the procedure carefully to see how the water on Earth is divided among the reservoirs you are studying.
1) Make sure your group has: 1000 mL beaker filled with water (4) plastic cups (1) graduated cylinder (2) paper towel sections (1) toothpick (1) eyedropper/pipette
2) Label the cups: Glaciers Groundwater Other reservoirs Lakes
3) Label one section of paper towel Atmosphere. Label the second section of paper towel Rivers.4) Note that the full 1000 mL beaker represents all the water on Earth.5) Use the graduated cylinder and eyedropper to remove 17.4 mL of water from the beaker and
put it in the Glaciers cup. Place the cup aside.6) In the fourth column of the table, record how many mL of water are in the Glaciers cup, next to
the word Glaciers in the third column. 7) Use the graduated cylinder and the eyedropper to remove 16.9 mL of water from the beaker
and put it in the Groundwater cup. Record the amount of water in the cup on the table. Place the cup next to the first one.
8) In the Other Reservoirs cup, put 2 mL of water from the beaker, using the eyedropper. This will be 40 drops. Record this amount of water on the table.
9) Remove 1 mL of the water from the beaker, using the eyedropper, and place it in the Lakes cup. This will be 20 drops. Record the amount on the table.
10) Dip the toothpick into the beaker of water. Tap it on the Atmosphere paper towel. Repeat nine times so you see nine spots of water. (Use a pen to make a dot next to each drop, so that when the water evaporates you can see where it was.) The drop is about 0.009 mL but on your data table, record the amount as <1 mL (less than one mL).
11) Dip the toothpick into the beaker of water again and tap it two times on the Rivers paper towel. This is about 0.003 mL, but on your data table record it as <1 mL.
School/ CampusTeacher
7th Grade- CI 4 L 4
12) The beaker now contains about 965.4 mL of water. Label this beaker Oceans and record the amount of water in the table.
13) Line up all the containers according to the amount of water that is in or on them. Put the largest container on the left and smallest on the right. Be sure to include the paper towels.
14) Compare the size of these reservoirs. Explain anything that surprises you.
Reservoir Actual Size (km3) Amount of Water (ml) Size in Order (1-7)
Atmosphere 12,900
Glaciers 24,064,000
Groundwater 23,400,000
Lakes 176,400
Ocean 1,338,000,000
Other Reservoirs 329,090
Rivers 2,170
Total 1,385,984,510
School/ CampusTeacher
7th Grade- CI 4 L 4
Direction: Answer the following questions.
1. Fill in the data table below.
Water on Earth data
% of Earth covered by water
% of water in Oceans
% of freshwater in ice
% of freshwater in groundwater
% freshwater available at surface
2. Why is the water in glaciers and ice caps unusable?
HW: What is happening to the ice? Team:___________________
Directions: Actively read the following passage and answer the questions below.
Who is the iceman and why was he murdered?
The ‘iceman' was found in an Austrian snowfield in 1991. Covered by ice for 5000 years, melting ice revealed his body to explorers. As the ice melted, a man was revealed who had lived long ago, shedding light on his life and finally his violent murder. We now know that when The Iceman's body was discovered, he had with him a copper bladed axe. So rare and expensive was this item that scientists feel that his death could not have been a random attack or his killers would have stolen it. Instead the evidence suggests that his murder was likely to be political. The man's age and weapon indicate he was powerful, and as so little preparation went into his journey it is likely that he left his home in a hurry trying to escape from danger.
The case study shows that the ice has stories to tell. It also gives us a clue that some of the world's ice is melting.
What is happening to the world's ice - why is it melting?
The world's ice is melting, quite simply, as a result of climate change. Rising temperatures in the earth's atmosphere are being caused predominantly by the burning of fossil fuels - coal, oil and natural gas - in the operation of cars, planes, heating and lighting our homes, and so on. This releases carbon dioxide into the atmosphere which acts as an insulating layer - very much like a greenhouse - trapping solar insolation and raising temperatures at the earth's surface. Plants and trees absorb carbon dioxide for the process of photosynthesis, so are natural carbon ‘sinks'. As a result, deforestation contributes to the problem. During the 20th Century, surface temperatures rose on average 1C. As a result of this increase, snow and ice cover has decreased, releasing freshwater into the oceans. In the same timeframe global sea levels have risen between 10cm and 20cm. Without significant policy changes, global mean temperature is predicted to increase between 1.4 and 5.8C over the next century, with an equivalent sea level rise of between nine centimeters and 88cm globally.
In terms of the shrinking of glaciers, the impacts of climate change are being felt most severely at the poles. Rising temperatures are causing the ice caps to melt in both Arctic and Antarctic regions. The Arctic has lost a third of its ice since the 1970s and 2007 was the worst year on record for ice cap loss. Some scientists are predicting further acceleration in melting, and have even suggested that there may be ice-free summers in the Arctic as soon as 2030.
As a result of the melting of polar ice caps, sea level is rising globally, creating a flood risk for coastal areas and many world cities, such as New York and London, both of which are located on the flood plain. According to an Australian study, sea levels have risen by almost two centimeters every year since 1870, in line with temperature rises over the same period.
How does ice tell us the secret of why it is melting?
School/ CampusTeacher
7th Grade- CI 4 L 4
It is the ice itself that has helped us to solve the mystery of why the ice is melting. Trapped air that is found in very old ice is analyzed by scientists to determine how carbon dioxide levels have changed over time. Ice cores are cross-sections drilled through the snow and ice. They allow us to look back in time. Over the past few decades, several long cores of ice between three kilometres and four kilometres long have been pulled up from the Greenland and Antarctic ice sheets to investigate long-term climatic change. Parts of the Antarctic ice are an amazing 500,000 years old. The ice was taken to a laboratory and melted, releasing bubbles of ancient air. Changes in air content - especially hydrogen - were then analyzed, showing scientists how temperatures have warmed and cooled over time.
The pockets of air trapped within the ice enable scientists to reconstruct the gaseous composition of the atmosphere in the past, notably the concentrations of carbon dioxide (CO2). The ice can also be examined for concentrations of dust, volcanic ash and various chemicals - all giving evidence of what was in the atmosphere at various times in the distant past.
1. Why is the ice of our ice caps and glaciers melting? Explain by giving 1 piece of evidence
