Science Experiments

Whether or not you write down an hypothesis, if you conduct an experiment, you naturally have a hypothesis since you are trying to find the answer to something and have some sort of expectations.

If available, a small, glass graduated cylinder would be best. Next best would be a test tube or any clear or semi-transparent cylinder/ small plastic recycled container/bottle. If an eyedropper is not available, recycle a milkshake straw to move/transfer small quantities of a liquid. Place the bottom end of the straw in the liquid almost to the bottom. Then hold your thumb tightly to the top end of the straw and lift out of the liquid. When you remove your thumb the contents will spill out of the bottom of the straw.

Change in temperature, dT,=1/m, where m is the amount of water, in kilograms.

Depends on how much kilograms of water you have. The equation to use is Q=cm(dT), where c is the specific heat capacity of water (conventional use puts it 4186 J/(kg*C degrees)), m is the mass, in kilograms, of the water you're heating, dT is the amount of degrees, in Celsius (or Kelvin), that you want to heat the water by, and Q is the amount of energy needed, in Joules. 1 kilocalorie equals 4186J, solving for change in temperature (dT), dT=Q/(cm). Substituting in Q and c gives you dT=1/m. If you do not know the mass, but only volume, m=pV, where p is the density of water (convetionally 1 *10^3 kg/m^3) and V is the volume of the amount of water you have in m^3.

The scientific method is a scientific method for systematically acquiring new knowledge. The scientific method is typically applied to experiments, involving taking a hypothesis and using it to get applicable results.

OH- (note the negative charge) is the hydroxide ion. This ion consists of a deprotonated water molecule; it acts as a base.

OH (typically denoted ROH) can also denote a hydroxyl group, which is a common functional group in organic chemistry. For example MeOH is methanol, CH3OH.

No. Lithium is a solid at room temperature.

I'm doing my homework and i looked up this question but I am putting the answer as the experimental variable

Solid water is ice, and is therefore much colder than liquid water. It is also less dense, and as a solid it is harder and stronger. Liquid water takes the shape of its container, whereas solid water retains its shape always, and liquid water can draw itself up thin tubes by capillary action.

Stating the problem usually calls for asking Why? or How?.

Observation: My eyes water when I cut onions.

State the problem: Why do my eyes water when I cut onions?

Density is a derivation of the quantity of matter (mass) in a given space (volume). At the temperature of 25 degrees Celsius water has a density of 1.00 gram per cm^3, while gold (Au) in comparison is 19.32.

Hypothesis is examined very closely to see what it predicts, and the predictions are then rigorously tested. If the predictions are not supported by the results of experiments, the hypothesis is rejected but if they are confirmed, the hypothesis is supported.

Haemophilia (also spelled hemophilia) is genetic disorder. It is more licely for a male to get it than female.

About one of 5,000-10,000 male babies are born with Haemophilia A. About one of 20,000-34,000 male babies are born with Haemophilia B.

A variable means that something that you can change, measure, or keep the same. Example: Responding variable: The variable you can measure. Controlled variable: The variable you keep the same. Manipulated variable: The variable that you change.

The phrasing of the question reveals a basic misunderstanding of the term "weight." Here is a famous trick question: Which weighs more, a pound of lead or a pound of feathers? Many people who answer quickly without thinking say the lead weighs more. That is, of course, silly. A pound is a pound is a pound. A pound of lead weighs exactly the same as a pound of feathers. But a pound of lead will occupy far less volume than a pound of feathers because the lead has greater density than the feathers. So let's look at the water-ice comparison. If you had asked, "Does a cubic foot of ice weigh less than a cubic foot of water," we could have answered, "Yes. Because ice is less dense than liquid water, equal volumes of the two substances will have different weights. So, a cubic foot of ice weighs less than a cubic foot of water."

Without a control group, what would you compare your results to? How would you know if the treatments had any effect? Without a control group, there is no basis for knowing if a particular result is due to the variable being tested or to some other factor.

The control group gives a set where the expected outcome is known. So when a variable is changed and if the outcome is the same as the control group, then we know to try a different variable.

Technetium is not really dangerous. Since doctors will often use Technetium 99 as a radioactive tracer. It may be radioactive but its decay is slow and will produce a minute amount of gamma rays.

The independent variable is the part of the experiment that is being tested or the part that is changed by the person doing the experiment. The dependent variable is the part of the experiment that is affected by the independent variable.

An Epppendorf pipet is what is called a constant volume pipet. It consists of a barrel with a a push button on one end and a stem on the other. You attach a single use disposable tip to the stem. Some models allow you to set the volume to be dispensed, some are not adjustable. In use, , you depress the push button to the first stop, insert the tip into the liquid to be pipetted, and release the button smoothly to draw up the liquid. Then, transfer the pipet to the receiving vessel and depress the button past the first stop to the second stop, this dispenses the liquid and blows out the last drop to insure accuracy, then discard the tip before the next use. Every time you draw up liquid, you get the exact same volume, with very high precision.

They're heavier than water is.

The density of the metal is greater than water. The density is the weight per volume. Any material that has a greater density of 62.5 pounds per cubic feet (1000 kg per cubic meter) will sink.

whether the data supports the hypothesis

Stirring will mix up the solvent, meaning parts of the solvent that were saturated are moved away from whatever is dissolving, and it can dissolve with other parts of the solvent that are not saturated.

Three circular discs are rigidly fixed to a common axis followed by four fixed discs above, below and between the oscillating discs all at equal distances and close together. Then the surrounding gas can then be calculated from the logarithmic decrement of amplitude.

Basically, your material has to absorb the sound.

Lead makes a good material- it takes a lot of energy for a sound wave to pass through a sheet of lead.

If you can't afford lead, or it is too heavy to use, use layers of material with different densities (sound waves lose energy at interfaces (the place where different materials touch).

if your on a budjet then cardbored egg trays with cotton wool inside works

or even better a sheet of cork with a layer of leather over it an then plasterboared