Exercise : Materials Year 5

1. Which of the following examples is a solid?
A. Fruit juice
B. Cooking oil
C. Oxygen
D. Sponge

2. The process in which cloud is formed is called
A. melting.
B. freezing.
C. condensation.
D. evaporation.

3. ______________ can changes the ice cube to water.
A. Melting.
B. Freezing.
C. Condensation.
D. Evaporation.

4. Raju did an experiment on the evaporation of water. He put 50ml of water in each container at the beginning. After 3 hours the results of the experiment shown in diagram below.

(a) What is the aim of the investigation?



(b) State two variable that should be kept the same.



(c) Give a reason (inference) based on the observation above.


(d) In this investigation, state the following variable:-

i. What is changed :

ii. What is measured :


(e) State the relationship (hypothesis) between the two variable that your mentioned in (d)



(f) State the relationship (hypothesis) between the surrounding temperature and the rate of evaporation.



(g) What conclusion can be made in this investigation?

Foods: are they Acid or Alkaline-forming?

Note that a food's acid or alkaline-forming tendency in the body has nothing to do with the actual pH of the food itself. For example, lemons are very acidic, however the end-products they produce after digestion and assimilation are alkaline so lemons are alkaline-forming in the body. Likewise, meat will test alkaline before digestion but it leaves acidic residue in the body so, like nearly all animal products, meat is classified as acid-forming.

It is important that your daily dietary intake of food naturally acts to balance your body pH. To maintain health, the diet should consist of at least 60% alkaline forming foods and at most 40% acid forming foods. To restore health, the diet should consist of 80% alkaline forming foods and 20% acid forming foods.

FOOD CATEGORY	Alkaline	Acid	High Acid
BEANS, VEGETABLES, LEGUMES	Vegetable Juices, Parsley, Raw Spinach, Broccoli, Celery, Garlic, Barley Grass	Pinto Beans, Navy Beans	Pickled Vegetables
FRUIT	Dried Figs, Raisins	Canned Fruit
GRAINS, CEREALS		White Rice, White Bread, Pastries, Biscuits, Pasta
MEAT		Fish, Turkey, Chicken, Lamb	Beef, Pork, Veal, Shellfish, Canned Tuna & Sardines
EGGS & DAIRY		Eggs, Camembert, Hard Cheese	Parmasan, Processed Cheese
NUTS & SEEDS		Pecans, Cashews, Pistachios	Peanuts, Walnuts
OILS
BEVERAGES	Herb Teas, Lemon Water	Wine, Soda/Pop	Tea (black), Coffee, Beer, Liquor
SWEETENERS, CONDIMENTS	Stevia	Milk Chocolate, Brown Sugar, Molasses, Jam, Ketchup, Mayonnaise, Mustard, Vinegar	Artificial Sweeteners

Why We Need Clean Water

Ten Reasons Why We Need to Clean Water

1. Clean water is vital to the human body.

The human body is 50 to 70 per cent water, and needs a regular supply of clean water to maintain health. We need clean drinking water. We need clean water for cooking and making beverages. Healthy eating and clean water go hand in hand. We must work to clean water worldwide in order to maintain sufficient sources to supply this need.

2. Clean water is vital to our food.

If we fail to clean water and keep it clean, we will be shut up to a diet of contaminated food. Not only fish, but other meats, fruits, and vegetables will deliver contamination to us. If we want healthful, clean fish to leap forth from rivers, streams, and oceans, we will have to clean water. If we want healthful, organic produce, we will have to clean water used to irrigate produce.

3. Clean water is vital to human health.

Clean drinking water is vital to health, yet the UN and the World Health Organization (WHO) report that 1.1 billion people around the globe lack access to clean drinking water. The health consequences are devastating. The UN attributes 2.2 million deaths annually to poor water and sanitation. If we clean water, provide better sanitation, and teach people how to keep water clean, future generations can enjoy longer and healthier lives.

4. Clean water is essential for water sports.

A swimmer in clean water is safe from illnesses and diseases produced by contaminated and toxic water. A surfer does not have to fear swallowing water in a wipe out. Boaters and others who use our water for recreation can relax without concern about pollutants. Yet, 27 years after the passage of the 1972 Clean Water Act, 40% of our rivers, lakes, and estuaries were still too polluted for safe swimming and similar water sports.

5. Clean water is essential for fish and other wildlife species.

As humans, we must consider the needs of fish, whales, water fowl, and other wildlife species that live in water. We must clean water when there are oil spills, of course, but we must also work to clean water flowing into our oceans, lakes, rivers, and streams. We must clean water for wildlife that does not live in the water, but depends on clean water for health and cleanliness.

6. We need to clean water to cut down on our carbon footprint.

The emissions involved in producing bottled water are astounding. Pablo Päster, Sustainability Engineer and MBA, did a thorough and exhaustive study of the cost of bringing a single liter of Fiji Water to America. He found that bottlers use nearly seven times as much water to bottle it than you actually drink. The total amount of water used to produce and deliver one bottle of imported water is 6.74 kg! In the process of making the bottle, getting water into the bottle, and delivering it to you, 250g of GHG emissions were released.

7. We need to clean water to cut down on refuse.

Each plastic drinking-water bottle takes hundreds of years to biodegrade in a landfill. Many plastic drinking-water bottles litter the countryside. Some will be recycled, but the recycling process is said to pollute the environment with toxic carcinogens. If we clean water so that it is truly free of contaminants, additives, bacteria, and virus, people are less likely to rely on bottled water.

8. Clean rain and snow are not givens.

Rain is just one step in the water cycle. Pure rain does not automatically fall through the universe, filtered by the atmosphere and delivered from pure clouds. Neither does pure snow. The rain, snow, and other precipitation we receive find their way into the sky from bodies of water on earth. If we fail to clean water on earth, we will have increasingly polluted precipitation. Polluted precipitation is harmful to everyone and everything on which it falls.

9. We need clean water for all-around cleanliness.

Whether it's your laundry in the Maytag washer, your carpet beneath the cleaning machine, or your body under the shower, clean water is necessary for all-around cleanliness. From early preschool years onward, children are taught proper hygiene - and it depends on clean water.

10. The consequences of inadequate access to clean water are too great.

Many have expressed growing concern that water wars are more likely in the future than current battles for oil. Where access to clean water is the very essence of life, "no water" may mean "no peace." A failure to clean water now may result in global warfare for future generations.

You may be able to add more reasons. You may substitute different reasons, but the bottom line is still the same. We need to clean water.

How To Keep Our Water Resources Clean

How is Water Pollution Caused?

Although certain natural processes may cause some of the water pollution, however, human activity is the largest cause of our seas, rivers and lakes getting polluted. We need to use water everyday both in our industries as well as our homes. We get this water from groundwater sources, rivers, and lakes, and after using it, and often contaminating it, most of this water gets back into the rivers, lakes, and oceans.

The used water from agricultural and industrial practices, and household use create wastewater, also referred to as sewage. If this is allowed to flow back into water systems without being treated, it causes pollution, which results in harming both humans as well as animal life. Water also gets polluted when there is a runoff of rainwater from industrial, agricultural, and urban areas, which flow directly through stormwater drains into water systems without any treatment.

The disposal of sewage is a major problem in developing countries where there isn’t adequate sanitation in large areas, thus carrying disease causing bacteria and viruses into sources of water. In countries that are developed, people often flush pharmaceutical and chemical products into their toilet.

Some of the other causes of pollution are oil spillages and dumping in oceans, dumping litter into streams, rivers, and oceans such as cardboard, newspaper, foam, Styrofoam, plastic packaging, aluminum, glass, and so on. Some of these take a very long time to degrade, e.g., plastic packaging can take 400 years, Styrofoam takes 80 years, foam takes 50 years, and aluminum takes 200 years.

Nuclear waste, atmospheric deposition, and underground storage leakages are some of the other causes of water pollution.

What are the Ways to Prevent Water Pollution?

While we need to see to it that the government is stringent about seeing to it that there are adequate treatment plants to treat sewage, and seeing to it that industries have treatment plants and nuclear plants have proper waste storage systems for radioactive material, and so on, there are many things that we can do individually to prevent water pollution. Given below are a few ways to prevent water pollution:

• Toxic products like paints, automobile oil, polishes, and cleaning products should be stored and disposed off properly. As a matter of fact, it is better to use non-toxic, products for the house as far as possible. Also, never dispose off such products by throwing them into your toilet or sink.
• Dispose off your trash in a proper manner and try and incorporate the recycling habit as far as possible. Non-degradable products like tampons, sanitary napkins, and diapers should not be flushed down the toilet, for these can end up damaging the process of sewage treatment, and usually end up as litter on beaches.
• Refrain from throwing litter into streams, lakes, rivers, or seas. If you do spot litter on beaches or in water systems, after ascertaining that it is safe, collect them and dispose off them in any nearby waste disposal system.
• Try using environmentally friendly household products like toiletries, soap-based household cleaning material, and washing powder as far as possible.
• Try using natural fertilizers and pesticides as far as possible, or if not, do not overuse them or over-water gardens and lawns. This will help in reducing the pollutants that get into water systems due to runoffs.
• Automobile oil should be re-used as far as possible. Also, it is important to keep your automobile well maintained in order to prevent leakages of toxic fluids like antifreeze and oil.
• Also, actively conserve water by turning the tap off when you do not need running water, such as while brushing teeth. Apart from preventing water shortages, it lessens the amount of water that needs to be treated.