SKILL BUILDER Sequency

Sequency Arrange the fallowing list of solutions in order from most basic to most acidic.

Tomato juice, pH 5                                           Milk of magnesia pH, 10.5
Baking soda, pH 9                                            Seawater, pH 8
Lemon juice, pH 2                                            Drain cleaner, pH 13


The arrange for list of most basic to most basic is following:

Drain cleaner, pH 13 is highly basic
Milk of magnesia, pH 10.5 is strongly basic
Baking soda, pH 9 is basic
Seawater, pH 8 is lightly basic
Tomate juice, pH 5 is acid
Lemon juice, pH 2 is is strongly acid

Acids and Bases

Questions about Acids and Bases

1. What is pH?

pH is a measure  of hidrogen ion concentration of a solution .

Solution with a high of hidrogen ions have a low pH and solution with a low concentration of hidrogen ions have high pH.

       2. What are Ph values?

The pH scale measures the degree of acidity of an object. Objects that are not very acidic are called basic. The scale has values ranging from zero (the most acidic value) to 14 (the most basic). As you can see from the pH scale above, pure water has a pH value of 7

 Do these values depend on something ? Explain.

Depend onthe amount of Hidrogen ions into a sustance is


    3.  Check Chart 3.2 about acids and bases

The table shows the acids such as chlorohydric, sulfuric and nitric; indicates the highest concentration of hydronium ionsWhen acids such as acetic, carbonic and ascorbic are weak, their concentration is lower. Vinegar, and vitamin C for example.Strong bases are related to the greatest amount of hydroxide ions.Strong bases are sodium hydroxide and potassium hydroxide.The weak bases are Ammonia and aluminum hydroxide

     4. What is neutralization?

Is the interation is that occurs between acids and bases in which propieties of each are canceled out by the other.

Examples:

In case of wasp stings, these insects inject the body with a basic substance or alkali to the skin and to neutralize it and relieve pain can be washed or put some vinegar on the affected surface

Plants cannot grow well in acidic soil.
Lime fertilisers such as powdered lime, CaO , limestone, CaCO3 or asshes of burnt wood are added to the soil neutralise it acidity.

Skill Builder

Homework Science

Separating and Controlling Variables 

Scientists pay close attention to controls, dependent variables, and indedependent variablesn when tey desingn experiments. 
How to identify controls and variables?


See if you can identify the controls and variables in the following Skill Activity:


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 untill all the salt has disolved.
4. Take the temperature of the water and of the salt solution.
5. How did dissolving salt in one beaker affect the water temperature?
6. What were the controls? Variables?

The indepent variable, also know as manipulated variable, is at the center of any quantitative experimental desing.

In any real experiment, an investigator manipulates an indepent variables to influence one or several dependent variables

The controls are factor that are kept the same, provinding a basis for comparison.

In the previous experiment the controls and the dependent and dependent variables are the following:

Independent variables:

- The amount of water

- The amount of salt in the water.

Dependent Variables:

- The rate of dissolution of the salt depends on the temperature of the water

The controls of the experiment are:

- The shape and size of beakers

- The amount of water


In Practicing the Skill
1) The Controls
- Ten grams of sugar
- The amount of water
-

The Independent Variables
-  The temperatura of water
-  The quality of water

The dependent variables.
- The rate of dissolution of sugar

2) The dependent variable is the increase the fuel mileage of our family car

Skill Builder

Comparing and Constrasting

Compare and contrast the following types of solutions: the active material in a hellium-neon laser, bronze, cloudy ice cubes and ginger ale.

• The helliun-neon laser is a solution of two gases: Helliun gas and Neon gas
• The bronze is a solution two solids: coper and tin
• Cloudy ice cubes is solution of liquid and gas
• Ginger ale is solutio of liquid and gas

1. Bronze (copper - tin) contrast

        Heffave bright luster

         Is malleable

         Good heat conductor

•     Hellium contrast ( material in helluim - neon laser)

            Does not have luster,

            Different colors,

            Is soft gas,

            Bad conductor of electricity

• Comparing between hellium and bronze.

        There is not any compare about

 2.   Compare between cluody ice cubes and ginger ale

       Both could be liquid or gass

• Contrast

     The (liquid) ginger ale takes the form of any container while the gas just expanded

atom  model

https://drive.google.com/file/d/0Bx4Kf_VzADFmb0Q0bEVQTXh4alU/view?usp=sharing

https://drive.google.com/open?id=0Bx4Kf_VzADFmb0Q0bEVQTXh4alU

https://drive.google.com/open?id=0Bx4Kf_VzADFmRG5kTHFyWTJNU3M

Science and Technology

Comparing and Contrasting:

I think that a modern scientifist and scientist from 1800's could comunicate their information with other scientis of other time using some instruments like microscope or a balance, but also, they could anlyze together by nothing similirities and differences between the events they observes. For throughout a comparing table.

ENERGÍA