Objective 1: Understanding Solutions
1. What are the characteristics of solutions, colloids, and suspensions
In order of smallest to largest particles:
solutions- particles equally spread
colloids- larger particles; eventually settle out
suspensions- very large particles; settle out quickly
2. What happens to the particles of a solute when a solution forms? The particles are typically mixed with a solvent (solvent is normally in a larger quantity) and the particles dissolve. i.e. sugar water (sugar=solute, water=solvent [water is the universal solvent])
3. How do solutes affect the freezing point and boiling point of a solvent? Solutes lower the freezing point and raise the boiling point of a solvent.
4. Suppose you mix food coloring in water to make it blue. Have you made a solution or solution or a suspension? Explain. I am going to speculate and say that it creates a solution, because the particles are distributed equally. If they weren't equally spread out would the water be entirely blue? I hypothesize that it would not be entirely (visually, without a microscope, magnifying glass, etc.) blue.
5. What effects do solutes have on a solvent’s freezing and boiling points? Solutes lower the freezing point and raise the boiling point of a solvent.
Aren't the questions in red basically asking the same thing?
Objective 2: Concentration and Solubility
1. How is a concentration measured? With the pH scale:
2. Why is solubility useful in identifying substances? If something is soluble, it is defined as a substance that can be dissolved (i.e. sugar); also note that the word solute is very similar to the word soluble. If something is insoluble then it can not be dissolved. This is an important factor in identifying a substance because not all substances are solubles. So by using process of elimination given the information that a substance is able to dissolve scientists are one step closer to identifying the given substance. Science is mainly a process of elimination and guess-and-check.
3. What factors affect the solubility of a substance? Temperature, pressure, polarity, molecule size and activation energy.
4. How does temperature affect the solubility of most solids? Heat starts to break up the bonds in a material, thus helping soluble the given substance.
5. How can solubility help you identify a substance? If something is soluble, it is defined as a substance that can be dissolved (i.e. sugar); also note that the word solute is very similar to the word soluble. If something is insoluble then it can not be dissolved. This is an important factor in identifying a substance because not all substances are solubles. So by using process of elimination given the information that a substance is able to dissolve scientists are one step closer to identifying the given substance. Science is mainly a process of elimination and guess-and-check.
Sorry but once again, can't the two questions in red be answered together?
Objective 3: Describing Acids and Bases
1. What are four properties of acids? They conduct electricity, taste sour, it's properties neutralize when combined with a base, and liberates hydrogen when confronted with active metals. 2. What are four properties of bases? They also conduct electricity, and when confronted with acids their properties are neutralized; unlike acids: they taste bitter and feel slippery to the skin. 3. How can you use litmus paper to distinguish an acid from a base? (Neutral) litmus paper turns red if the given substance it is confronted with is acidic and blue if it is basic (a base). 4. How might you tell if a food contains an acid as one of its ingredients? You can check the label to see if it mentions an acid, or use neutral litmus paper; it will turn red if it is acidic. 5. Why is it wise to wear gloves when spreading fertilizer in a garden? Well at the moment the best reason that comes to mind is the fact that many fertilizes contain animal waste, and no one really wants that on their hands... But I don't think that relates to the subject at hand, which is acids and bases. Based on this answer from Yahoo Answers: http://answers.yahoo.com/question/indexqid=20080508201726AAJBckx some
fertilizers contain weed killers and salts that when absorbed via skin, they can be potentiallydangerous.
Objective 4: Acids and Bases in Solution
1. Which ion is found in acids? a cation
2. Which kinds of ions do acids and bases form in water? Hydroxide atoms are formed.
3. What ions will the acid HNO3 form when dissolved in water? H+ and NO3
4. What does a substance’s pH tell you? It tells whether it is acidic or not.
5. If a solution has a pH of 6, would the solution contain more or fewer hydrogen ions (H+) than an equal volume of solution with a pH of 3? The hydrgen ions will be less because as the acidity increases, the hydroen ions increase as well. and 3 is more acidic than 6 , hence it has more hydrogen ions than 6.
Source:
http://answers.yahoo.com/question/index?qid=20080509000849AATJmpZ
Objective 5: Digestion and pH
1. What are the two parts of digestion?
2. How do those two parts differ?
3. People who have lost most of their teeth may have trouble chewing their food. How does this affect their digestive process?
4. What is the pH in your mouth? Stomach? Small intestine?
5. Why are pH variations in different parts of the digestive system important to the process of digestion?
Objective 6: Key Terms
Define:
2. Neutralization is a process that happens when an acid and a base are combined, and it results in both the acid and base loosing some or all of their properties.
3. An indicator is a tool in chemistry such as litmus paper that shows whether a substance has a high concentration of a chemical or whether the chemical is present in the substance at all.
4. When something is corrosive it has the ability to destroy or erode a substance. In chemistry acids are corrosive because they basically erode active metals, thus creating hydrogen.
5. Hydroxide ions are also known as hydroxyls. Hydroxyls are negatively charged atoms create by a Hydrogen and Oxygen link/covalent bond.
No comments:
Post a Comment