PAGE How much of the air supports burning ? — Is air a mixture ? How can we explain burning ? What is a flame? How can we prepare oxygen ? What is oxygen like? Why do some substances char? What is formed when What is carbon dioxide like? Why does soda water foam, or effervesce? - How does carbon dioxide put out fires ? How does carbon dioxide get into the air? How Why do we breathe? Why do we need ventilation ? Fresh air and tuberculosis. How do we ventilate our houses ? - How can we ventilate our bedrooms? - How to ventilate the schoolroom. Do we need moisture in How do we heat the house? Fireplaces. Stoves. How does a fire warm us? - Hot-air furnaces. Heating PAGE CHAPTER IX Are heat and temperature the same? Can heat be measured ? - - Is heat needed to melt ice? How does the body keep its heat? Why does perspiration cool the body? What is the weather? Of what is the atmosphere com- posed ? What causes dew and frost ? How are clouds our What is the earth like? What is the sky? Why do the heavenly bodies rise and set? What is the path of a . What are What holds the solar system together? Why does a body have weight? In what direction does the earth pull ? What is the density of water? Why does a body float? Why does a pendulum swing ? - What is a force ? What is a substance ? Can substances be changed ? Can water be changed ? What is an element? How can What is phosphorus like? What is a match ? — Ex- Where is water found ? What is water like? How does water boil ? How is ice made? How is ice cream frozen ? How do bodies of water affect climate? How does Why do we need so much water? How do cities get their water ? How do we get water in the country? What is plumbing ? What is a pump? - What is a force pump? — What are the dangers in water? get pure drinking water ? - What is a filter ? Can a city What is the earth's crust? What are the classes of rocks? How are stratified rocks formed ? What are How weathering? How is our soil formed ? What is the What are minerals? Is iron necessary to man? How is iron found? - How is iron prepared ? How is lead obtained? — How is copper obtained? - How are gold and silver found ? - What is 22-carat gold ? - How do men find precious stones? What is coal ? — What are Do we use science in the home? Where are acids found? - What makes a compound an acid ? What are bases like? What are the materials of clothing ? How are silk and wool obtained ? How is clothing washed? - How does soap work? — How is soap made? · What is dry cleaning ? Why do we need food ? What foods give us energy? What foods make us grow? What are the minerals in The Cooking and Baking of Foods Why do we cook food? Why are foods cooked in boil- ing water? What is broiling ? How do we fry foods? What is the baking of foods? Why is baking powder used ? What is yeast? · How does yeast act in making bread ? How do we can and preserve foods? How does drying preserve food ? · How is meat smoked ? - What are salting - |
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