hw #4

The picture represents a heterogenous suspension mixture where a heavier three atom compound sinks to the bottom and its made of two compouds.

3rd hw assignment

Chem homework #3

1. A physical property is a property that can be observed and measured without changing the chemical makeup of the substance.
2. Three physical properties of water are the freezing point, boiling point, and density.
3. The density of a liquid compares to the density of a solid because the density of a liquid tends to be less than the density of a solid.
4. A setting where u might experience water in all three forms is in a warm pool during winter. The snow outside the pool is a solid form of water, while the water inside the pool is in its liquid state, and the steam coming from the pool is water in its gaseous state.
5. Heterogeneous and homogenous mixtures are different because a homogenous mixture is uniform throughout where as a heterogeneous mixture is not.
6. In order to figure out whether gas or water is going to be the liquid on top of the other a person needs to find the density of each because the litter density will float to the top.
7. A medicine accompanied by instructions to “shake before using” is a suspension

b. Italian salad dressing is a suspension

c. Mayonnaise is a colloid

d. A cola soft drink is a solution

e. An oil-based paint is a suspension

f. Milk is a colloid

      8. This demonstrates that the air in a room is a colloid because if you can see the beam of light the particles are big enough to reflect the light but small enough not to be seen. Where as if the air was a suspension it would be to cloudy and the beam would be blocked.

       10. The mixture is a colloid because if the beam is visible then there are visible particles floating in the substance and because no particles settled on the bottom the particles are not big enough to be a suspension.

       11. A substance has a uniform and definite composition and distinct properties. Each element and compound is considered a substance.

       12.  a. CO is a compound

              b. Co is an element

              c. HCI is a compound

              d. Mg is an element

              e. Na HCO3 is a compound

              f. NO is a compound

              g. I2 is an element

Water pollution vs water shortages #2

I still believe that water pollution os worse than water shortages because water shortages, though hard to deal with, are bearable because u just have to limit the water usage in a home. Water pollution, however, is harder to get rid of and more difficult to deal with because the appearance of water may deceive many people into thinking its clear. Polluted water is more harmful than a water shortage in many cases because water can always be trucked in but when there is already a water source many people don't think to bring in more water; even though, the water that is available to the people living in an area may be polluted.

electrical conductivity

1st Vocab list on A and B

Chem Vocab

Chem Vocab

Filtration- solid particles are separated from a liquid by passing the mixture through a material that retains the solid particles and allows the liquid to pass through.

Filtrate- the liquid collected after filtration.

Adsorbs- attracts and holds on its surface

Percent recovery= percent of orginial foul water sample recovered as purified water.

Histogram-graph- graph showing percent recovery obtained by all groups in the class

Range – difference between the largest and smallest caules in a data set.

Average- add all the values together and divide by the total number of values also called the mean value.

Median- list all percent recovery values in either ascending or descending order then find the middle of the list. Ex. 1 2 3 4 5 6 7       If even number of data points, take the average of the two values                   nearest the middle

                                    Median

Distillation- another water purification technique

Electrical conductivity- focuses on the presence of dissolved, electrically charged particles in the water.

Tyndall effect- particle are too small to see but big enough to reflect light coming from a beam. (tests clarity and purity.)

Direct water use- that which can be directly measured

Indirect water use- hidden uses of water that you may never have considered.

States of water

Gaseous state- water vapor in the air

Liquid state- regular water (lakes, rivers, oceans, clouds, rain)

Solid state- ice, snow

Surface water- water from a river or other bodies of water

Ground water- from a well; ground water must be pumped to the surface.

Aquifer- a water-bearing layer of stone, sand, and rock. Wells are made above them and obtain their water.

Foul water purification methods

Oil-water Separation- way to purify water

Sand filtration- way to purify water

Charcoal adsorption and filtration- way to purify water

Vocab for B.1-B.4

Matter- anything that occupies space and has mass

Physical properties- properties that can be observed and measured without changing the chemical makeup of the substance.

Density- the mass within a given voume.

Freezing point of water is 0 degrees C

Aqueous solution- water based solution

Mixture- when two or more substances combine, and yet the substances keep their individual properties

Heterogeneous mixture- composition not uniform throughout.

Suspension- type of heterogenous mixture when the solid particles are large enough to settle out of can be separated by using filtration.

Tyndall effect- the scattering of light

Colloid- small, solid particles still in water type of mixture

Homogenous mixture- particles that become uniformly mingled with the particles of water

Solutions- homogeneous mictures consist of one or more solutes and a solvent

Solute- the dissolved substance

Solvent- the dissolving agent

Elements- one type of atom

Compounds- two or more types of atoms chemically bonded

Particulate level- at the level of its atoms and molecules

Atoms- often called the building blocks of matter. Matter made up of only one kind of atom

Element- matter that is made up of only one kind of atom

Compound- a substance that is composed of the atoms of two ro more elements linked together chemically in certain fixed proportions.

Chemical formulas- elements are represented by these

Substance- each element and compound is considered by these; each has a uniform and definite composition.

Molecule- smallest unit of a molecular compound that retains the properties of that substance

Example of element is oxygen

Water is a molecular compound

Second homework assignment

Questions 1-4 from page 22

1. Three water uses that you could do without are washing  cares, floors, windows and pets; washing clothes, dishes; and watering indoor plants, outdoor plants, and the lawn.
2. One activity that you could not do without is bathing, showering, washing hair, and washing hands
3. You could reduce water use for bathing by taking showers instead of baths and taking quick showers where you only turn on the water to rinse the soap out.
1. You can use impure water to water the lawn and any plants and to flush toilets.
2. This water can be taken from showers or hand washing and washing clothes.

Questions 3-7 from page 23

1. The manufacture of filter paper is an indirect water use because while working with the paper you never actually come in contact with the water that was used to help make it. The remoistening of sand and gravel is a direct water use in the foul-water lab because the water is seen and poured in the lab. The use of water to cool the distillation apparatus is a direct used of water because we came into direct contact with it.
2. To “purify” water means to make the water so clean that there are no particles or anything other than water molecules left.
3. Three techniques for purifying water: Oil-water separation, sand filtration, and charcoal adsorption.
4. Oil, solid particles, odor, and any other impurities were removed from my foul-water sample.
5. The procedure used in the foul-water laboratory investigation could not convert seawater to water suitable for drinking because salt could not be filtered out through the three processes used. The additional purification steps needed to make seawater suitable for drinking are distillations and added steps to fully purify water.

Polluted water vs. No water at all

I believe that polluted water is worse than no water at all because the people obtaining and drinking the water may not know that the water is contaminated. Yet because that may be the only source of water near or accessible to them, they may believe that they can drink it. However, if the water is polluted the people that drink the water could become sick and lose fluids; therefore, they become more dehydrated and could possibly even die.