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Science Experiments
Experiments often conducted by students to test different scientific theories and hypotheses
11,111 Questions
Why does tap water freeze before salt water?
Short Answer:
As you lower temperature, pure water freezes first at exactly 0 degrees
Centigrade or 32 degrees Fahrenheit. (That is part of the definition of those temperature scale.)
When water has any impurity in it, the freezing temperature is lower. This is called "freezing point depression."
Explanation:
People say, "Pure water freezes faster than salt water," but what is more accurate is to say that salt water freezes at a lower temperature than pure water. If you cool two identical samples of water, one pure and one salty, then temperature of salt water has to be lowered further to freeze, so it takes longer.
Tap water or any form of fresh water usually has such a small quantity of impurities present that the decrease in freezing temperature is a tiny fraction of a degree and not noticeable without specialized equipment.
Once you get to a percent or two of impurities in water, you start to see a degree or two change in freezing temperature. The specific change depend on what impurity you put into the water, but the more you put in, the lower the freezing temperature gets.
The cause of freezing point depression is a result of the disruption of the perfectly regular arrangement that water molecules want to make when they form solid crystalline water, i.e.
pure ice. Basically all pure solids, want to form some kind of perfect crystalline arrangement of their constituent atoms or molecules when cooled to a low enough temperature, i.e.
the freezing temperature. Such a perfectly regular arrangement is disrupted by impurities, large impurities or charged impurities being more disruptive for water. As a result of the disruption the temperature must be lowered further before the energetics and the forces between particles becomes favorable enough to form the solid.
So, impurities in almost any material will cause a lowering of the temperature at which the material changes from a liquid to a solid.
Because most of us would be dead from famine, disease, or simply be working on a farm somewhere.
- Scientists are important because they help discover new things.
Why does metal expand when heated?
The over excited metal-molecules are rapidly accelerating when the metal is heated, and this excitement caused them to collide more frequently than usual and in more drastic and random motions. The increase in kinetic energy promotes expansion.
Blood plasma is 95% water. Other components of blood plasma include clotting factors, proteins, and glucose; blood cells are not part of the plasma.
How can sugar and water be separated?
Sugar and water can be separated by using a couple different methods. One method is by using an apparatus for distillation. Another is by using evaporation.
I DONT KNOW THE AMSWER, BUT THE UPSIDE ONE IS FULL TRASH!!!
Water, AKA the universal solvent.
universal solvent is water a solute is like kool aid
water, oxygen, acids, turpentine.
Water
Water is the most commonly cited example of a solvent. Other common examples are hexane, ethanol, and ether.
A slovent dissolves a solute, a good example would be sugar (the solute) and water (the solvent) mixing together. A example of a solvent would be water, an example of a solute would be salt or sugar.
Some solids are soluble in water , some are not . Some solids are soluble in gasoline, others are not. Not all solids are soluble in a liquid. Liquids can dissolve a solid. There are some kinds of solids that can dissolve in a particular kind of liquids. Water is however called the UNIVERSAL SOLVENT because it almost dissolve all subtances in a certain degree.
Examples of Solvents : Water , Gasoline , Vinegar , Alcohol , Kerosene
What is random assignment in science experiments?
There is no purpose.
ZeeNOObster is wrong. An experimenter would use random assignment/placement is such a case that he/she may not have a large sample and wants to make sure that some attribute is evenly divided into the groups.
example: some sort of study where IQ is of importance. To make sure that participants IQs are evenly distributed among the groups, the researcher would find out the participant's IQs and then randomly assign the top IQs to different groups, then moderate IQs and followed by low IQs. This is a simplistic way of looking at random placement
What does the gel in a 'vacutainer' tube consists of?
Some vacationers contain additives coated along the inside of the container without any gel. The gel in a vacationer is an intermediate density between blood cells and serum so that when centrifuged, the gel can keep the blood cells and serum from remixing. The gel consists of semi-solid inert gel composed of a number of compounds.
Enhancing the action of an agonist without having an individual effect itself.
What are the ingredients of the works toilet bowl cleaner?
The main ingredient in The Works toilet cleaner is hydrogen chloride. That is hydrochloric acid when mixed with water.
What other things dissolve in water?
Some things that dissolve in water are sugar, soda, food coloring, chocolate syrup, and food particles. Other things that dissolve is salt, vinegar, coffee powder, and copper sulfate.
Is dropping water on Lincoln side of penny a valid experiment?
Not really, the better expiriment would be if you used both sides of t he penny and compare all of your trials.
What metric measurement is used to measure liquid?
Liquids are usually measured in Liters (l) which are just slightly larger than a US quart.
Smaller quantities are often measured in milliliters (ml).
Note, many of the units in the metric system have other equivalent measurements. So, a liter is equivalent to a cubic decimeter, and a liter of water will weigh 1 kg (at 3.98°C, 1 ATM).
1 ml of water weights 1 gram (gm), and occupies 1 cubic centimeter (cc or cm3).
I want to make a science fair project about computer viruses. What recommendations do you have?
Its not really a science subject is it really?
Best i can come up with is by combining on how humans can get sick witohut protection and it works the same with computers. inform your class or whoeever its getting presented to that if they want their personal information to be safe they have to be careful with what they download. And with all these file sharing websites its easier to get than it seems.
Maybe finish with possible solutions should they ever run into a problem.
That's how i would go about it. We never really have science fairs were i live so that probably best i can give you ;).
Goodluck
The more intense the light, the greater the generated current will be. The important thing to understand about the photoelectric effect is that turning up the intensity of the light does not result in the electrons delivering more energy. Rather, a larger number of electrons are given the specific amount of energy that corresponds to the color of the light.
For economists substitutes for laboratory experiments often come in the form of?
natural experiments offered by history or untested theories
