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1.       What is PH? The pH is a measure if how acidic or basic the solution is. 2.What are PH values? The pH scale generally ranges from 0 to 14. ·          The acid solutions have lower pH values. ·          The basic solutions have higher pH values. ·          A Solution with a pH of 0 is highly acidic. ·          A solution that has a pH of 7 is neutral. ·          A solution with pH of 14 is extremely basic. Do these values depend on something?  Explain your answers. The pH of a solution is directly related to its concentrations of hydronium ions and hydroxide ions. ·          The acid solutions have more hydronium ions than hydroxide ions. ·          The basic solutions have more hydroxide ions than hydronium ions. ·          The neutral solutions have equal numbers of two ions. 3. Check Chart 3.20 about acids and bases. What can you explain about it? The pH scale is not a simple linear scale like mass o volumen. A change of a 1

Scientist pay close attention to controls, dependent variables, and independent variables when they design experiments. Do the Chaper 3 Skill Activity on page 844 to learn how to identify controls and variables. How to identify control and variables. Procedure 1. Pour the same amount of water into two beakers. 2. Take the temperature of the water in each beaker to make sure the temperature are the same. 3. Add salt to one beaker and stir the water in both beakers until all the salt has dissolved. 4. Take the temperature of the water and of the salt solution. 5. How did dissolving salt in one beaker affect th water temperature? 6. What were the controls? Variables? The scientist take great care to make sure only one factor in the experiment, the independent variable. The independent variable is the "cause" factor. The factor that changes as a result of the independent variable is called the dependent variable. The dependent variable is what is measured

COMPARING AND CONTRASTING The helium-neon laser is a gaseous solution compound by 2 gases:helium and neon The bronze is a solid solution. It contains 2 metals :copper and tin. Cloudy ice cubes is a solid gas solution. Ginger ale is a liquid gas solution because is a carbonated soft drink.

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Homerwork Science (20/08/2017) WHAT IS ENERGY? AND TYPES OF ENERGY The energy is abality to do some work. All things need energy to move, for example: The car uses energy from the oil and gas for its movement. There are several types of energy, for example: Electric energy such as light bulbs; heat energy such as the bonfires;  muscular energy of our body to move things ; the energy that comes from the sun is the solar energy; the energy of water is the hydel energy; the wind energy which produces electricity. Energy can be stored, por example: Sunlight is stored in the solar panels in the day and at night gives light to the light bulbs.