Bohr model

Flourine (F2) Bromine(B2)-

Iodine(I2)-

Batteries

Battries

Not all batteries need acid. There are many lead based batteries like:

1. nickel-iron
2. nickel-zinc
3. Nickel-metal Hydride
4. Nickel-Cadmium
5. Lithium Ion
6. lead calcium
7. lead antimony
8. AGM(Abosrbed Glass Mat Battery)

Bohr Model

The filling order (up to the elements in 20 Calcium is:

a)Two electrons in the first shell, maximum.

b)The next shell has up to eight electrons.

c)And also eight electrons for the next shell.

Dissolving, Concentration, Evaporation, Crystallization

Dissolving

-Is when particles diffuse through the liquid.

-This is a physical change NOT a chemical change.

For example when something like a sugar cube put in hot water, the particles slowly diffuse through the water. When it completely dissolves there is no solid left. This making the water know a solution.

Concentration

-This happens after dissolving.

If there is one sugar cube in a glass of hot water and it dissolves it is less concentrated. Or the solution has more dilute. But if there are three sugar cubes dissolved in a glass of water the solution has a higher concentration of solute.

Evaporation and Crystallization

Salt water can evaporate with time making the salt solution more concentrated. Eventually all the water will evaporate crystals of salt will begin to form called crystallization.

Distillation

The water evaporates, but the salt does not. On the side arm water vapours start to condense. This Fractional Distillation is good for separating solutions and recovering the liquid. There are different separation methods like evaporation or filtering.

Chromatography

The picture shows what a dot of felt pen on paper looks like when put in a beaker of water. It literally shows you the different colours mixed into this pens ink that's making the orange colour.

Settling Materials

Dirt in water settles, it is a example of a settling material.

Separation using Magnetics

Iron and sulphur=iron and aluminum

Filtration

Filters are all around you, especially in your kitchen. Ex. coffee, water, furnace, juices, sewage treatment, atmosphere.

States of Matter

Matter=is an object with mass and volume.
Solid- The particles squished together, slightly vibrating. The particles have broken natural bound but still are close together.
Liquid-There is more vibration between the particles and their natural bound is broken apart. (Vibration tends to force objects apart.) A Solid to a liquid is caused when more energy(vibration) is added.
Gas-The particles are know independent(no interaction) and are moving more faster. A liquid becomes a solid when more energy(vibration) is given to an object.

States of Matter

Pure substance

• some properties throughout
• constant compositions
• homogenise
• one type of particle(atom)

Element

• one type of atom
• cannot be broken down into simpler pieces
• found in periodic table
• H, He, Li, N, CO, Ne

Compound

• mode of two or more elements
• can be broken down
• some properties thorough out
• different properties from properties of the individual atoms
• Na Cl, Na1,H2O

Mechanical mixture

• can see individual pieces by eye
• salad, pizza

Lemon Battery

The way to make a battery is simple. Take and
acidic fruit/vegetables and stick a peace of aluminum and copper. (The more acidic the fruit/vegetables the higher the voltage.) Two lemons wont be able to turn on a light so try different fruits and peaces of aluminum and copper.
Think of anything with large amounts of acid in it, like vinegar.

Experiment!

Safety Open Book Test

1. An acute hazardous chemical shows its effect quickly.(a)
2. Acute hazardous chemical show their reactions within 3 hours. (a)
3. The lead compound contained in leaded gasoline is chronically hazardous.(b)
4. Moderate explosive symbol is (b)
5. The symbol indicating a moderate fire hazard is (b)
6. The symbol indicating a slight corrosive danger is (e)
7. The symbol indicating an extreme poison is (c)
8. The symbol indicating a moderate poison is (a)
9. The symbol indicating a low fire hazard is (d)
10. The symbols poisonous and flammable are very dangerous. (a)
11. An antidote is a material that counteracts the effect of a hazardous chemical. (c)
12. Which of the following products contains an acid? Vinegar (a)
13. Soaps and detergents help to remover oils from clothing because they are able to attractive forces with water and with oils.(a)
14.Compared to making suds in hard water, making suds in soft water requires a small amount of salt. (c)
15. Hard water is called "hard" because it contains high concentrations of dissolved substances.(a)
16. In which household situation below would you want to use a non-reactive chemical polishing brass.(a)
17. Symbol #1 indicates compressed gas. (a)
18. Symbol #2 indicates immediately, serious toxic. (c)
19. Symbol #3 indicates other toxic effects. (d)
20. Symbol #4 indicates corrosive. (e)
21. Symbol #5 indicates flammable & combustible. (d)
22. Symbol #6 indicates immediatly seriously toxic.(c)
23. Symbol #7 indicates bio hazard. (a)
24. Symbol #8 indicates dangerously reactive. (e)

Science Safety

Duffs survey writes about all the reasons for grade nines large amount of accidents happen in the article "Where and Why Science Accidents Occur." He writes reasons why grade nines have the largest number of accidents compared to all classes in junior and senior high school, and the solutions to the problem.
Duff three main reasons of why grade nines have the large amounts of hazards are because of overcrowding classes, immaturity, and the down points of younger classes.The overcrowding of the classrooms are because of the large amounts of students. This is why classes are changed into an ordinary class not meant for science, not requiring the equipment science classes need for safety. This has happened a few times and is a big possibility for the lower classes large amounts of accidents. The students immaturity is also a great motive, which is said by teachers to be a definite one. Though I question if this is an accurate, for grade nines are not the only ones how have trouble concentrating, understanding, and reading the directions. Therefore it be more thinkable to have said that grade eights are the immature ones. Then Duff writes of the down points of lower classes. Not only do more then 50% of the teachers lack work experience, but also curriculum is second hand from higher grades. This means weakly written laboratory instructions. Amazingly we hesitate to think that grade nines have had more accidents then other classes. Duffs three main reasons of grade nines large amounts of accidents are because of the overcrowding of the classes, immaturity, and the lower classes down points.
Duff then writes about the three main solutions to the problems grade nines are causing by, students reading pre-labs, giving pretests, and making sure they understand. The pretest should be read out by the students and questions almost to be required. When students are asked to read out they seem to understand and pay attention to what is said. Another possibility is to pretest them on the technique, procedure, and safety of the laboratory. It can be harsh to students giving them low grades, but they must realize the danger of how important it is to understand the safety. Lastly, the one most significant is making sure the students understand the safety rules. This can save accidents from happening. Duff's solutions of the large amount of problems grade nines cause are students reading pre-labs, giving them pretests, and making sure they understand safety rules.
Larry Duff's survey writes why grade nines have the largest amount of problems compared to all other levels throughout junior and Senior high school, and the solutions. He has written it in an article called, "Where and Why Science Accidents Happen."