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Science Experiments
Experiments often conducted by students to test different scientific theories and hypotheses
11,111 Questions
Does antifreeze affect plant growth?
Yes, antifreeze contains ethylene glycol which is toxic to plants. Exposure to antifreeze can damage plant cells, disrupt water balance, and lead to wilting and stunted growth. It is important to keep antifreeze away from plants to prevent harm.
What do the crust and upper layer of the mantle make up?
The crust and the hard uppermost mantle make up the lithosphere, which is the solid, rocky layer covering the entire surface of the planet and reacts to stresses as a brittle solid. The lithosphere ranges in thickness from 50 - 200 kmA and is fragmented into tectonic plates with boundaries where plates collide, diverge, or grind past each other.
A Wilson, M. (2000) Igneous Petrogenesis - A Global Tectonic Approach, Chapman and Hall, London.
What are the measurements of the heights of various plants in a experiment called?
In an experiment measuring plant heights, typically the heights of plants are recorded in either centimeters or inches. The measurements are taken from the base of the plant to the highest point of growth, such as the tip of the tallest leaf or stem. These measurements are important for assessing plant growth and health over time.
Does coconut water contain dissolved oxygen?
Yes, coconut water naturally contains dissolved oxygen due to the exposure of the coconut to air during its growth and maturity. This oxygen content may vary depending on factors such as processing methods and packaging.
In a controlled experiment what does a operational definition do?
An operational definition provides a clear and specific description of how a variable will be measured or manipulated in a study. It helps ensure that the variable is defined in a way that can be consistently applied and observed, making the results more reliable and replicable.
What are the materials for does hot water freeze faster than cold water?
The materials needed for the experiment are: two containers to hold the water, hot water, cold water, thermometers to measure the temperature, a freezer to freeze the water, and a timer to record the time it takes for each to freeze.
What is the difference between a hydrometer a hygrometer and a thermometer?
A hydrometer measures the specific gravity or density of a liquid, such as in testing the alcohol content of a solution. A hygrometer measures the relative humidity in the air. A thermometer measures temperature.
What is the heat of electricity?
Amount of electrical energy converted to heat energy when current flows through a conducting material.
According to Joule's Law, quantity of heat energy dissipated is given by,
Q=i2Rt
note- in power transmission, aluminum wires* are used to reduce the heat energy loss
- using a step up transformer,we increase the voltage and reduced in current to reduce heat loss.(heat loss is proportional to the square of current.)
* though silver is the material with minimum resistance,it is too dear to be used as transmission wires.
As a motorcycle takes a sharp turn the type of motion that occurs is called?
The type of motion that occurs when a motorcycle takes a sharp turn is called angular motion or rotational motion. This is when the motorcycle rotates around a point due to the combination of its linear velocity and centrifugal force acting on it.
Why do plants need to make food?
they need chlorofill (found in leaves in the palisade cells) light energy, water and carbon dioxide. the word equation for photosynthesis is:
carbon dioxide + water --light---chlorofill---> glucose + oxygen + water
Why does land absorb more heat than water?
Land heats up faster than water because it has a lower specific heat capacity, meaning it requires less energy to raise its temperature. Additionally, land is denser than water, allowing it to store and transfer heat more efficiently. Finally, land surfaces are often darker and absorb more sunlight, further contributing to their ability to absorb heat.
How do clouds form in the continuous process?
Sun rays hit water and it evaporates into air where it is carried up into the atmosphere. As the warm water vapor rises through the air a cooling process begins that forms clouds. The clouds dump the water back into ponds, lakes, and streams and the process continues.
What are the composition of minerals?
Minerals are naturally occurring inorganic substances with a specific chemical composition and crystal structure. They are composed of elements such as silicon, oxygen, aluminum, iron, magnesium, sodium, and potassium, among others. Minerals form through various geological processes and can be identified based on their physical properties, including color, hardness, luster, and cleavage.
How strong is the bite force of an adult polar bear?
An adult polar bear's bite force is estimated to be around 1200 pounds per square inch (psi), which allows them to easily crush through bone and thick ice to catch their prey like seals. This powerful bite force is essential for their survival in the harsh Arctic environment.
What is the average bite force of an orca aka killer whale?
The average bite force of an orca, or killer whale, is around 19,000 pounds per square inch (psi). This powerful bite allows them to effortlessly crush the skulls of their prey, including marine mammals such as seals and sea lions.
steam is water evaporating. It is caused when water molecules have enough energy to break free from the electromagnetic interactions that holds all the water together as a liquid.
Short form - steam is water so when it is hot it turns into gas.
The iceberg is melting due to rising global temperatures caused by climate change. Warmer temperatures are causing the ice to melt faster than it can replenish, leading to its gradual disappearance.
Describe the unique problems of cleaning up groundwater pollution?
Sometimes the only way to regain use of the aquifer is to treat the water at its point of use. For large water providers, this may mean installing costly treatment units consisting of special filters or evaporative towers called air strippers.
Catchy science fair project title?
It depends on the type of project. If it has something to do with wind turbines, for example, you could do "Gone With the Wind" or if it has something to do with green energy, you could do "Green with Envy". You might want to clarify your question if you want a more specific answer!
What is in RNA but not in RNA?
RNA is single stranded and has Uracil instead of Thymine.
DNA is double stranded and has Thymine, not Uracil.
Can Discoveries and ideas generated in one experiment be used for another experiment?
Yes, discoveries and ideas generated in one experiment can often be applied to another experiment. Researchers can use insights gained from one experiment to inform the design and implementation of subsequent experiments, leading to new discoveries and advancements in the field. This iterative process helps build on existing knowledge and push the boundaries of scientific understanding.
Dew forms when the temperature in the layer of air just above the Earth's surface matches the dew point. This causes the air to reach saturation, leading to water vapor condensing into liquid water on surfaces like grass or cars.
What are the five qualities of a good disinfectant?
- concentration
- pH
- contact time
- humidity
- temperature
- presence of organic matter
- type of microorganisms, numbers and presence of spores
- physical situation (surface type, suspension, etc.)
- contact available between disinfectant and microorganisms
- possible interaction between disinfectant and materials
- contact time allowable
- concentration
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Preparing Working DilutionsFollow the manufacturer's recommendations for dilution of concentrated disinfectant.- Prepare fresh dilutions daily
- Use clean, dry containers
- Use clean water for dilutions
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Common DisinfectantsChlorine CompoundsGenerally used in the form of sodium hypochlorite.
- Effective against a wide variety of microorganisms (vegetative bacteria and viruses). Preferred disinfectant for HIV and hepatitis viruses.
- Use at 0.1% as a general disinfectant.
- Less suitable in the presence of organic matter (such as blood). Concentration must be increased to retain action (0.5%).
- Effective between a pH range of 6-8.
- Strength decreases on standing (make fresh solutions daily).
- High concentrations corrode metal surfaces, and bleach and damage fabrics.
Ethanol (80% v/v ethyl alcohol) or 2-propanol (60-70% v/v iso-propyl alcohol) solutions are used to disinfect skin and decontaminate clean surfaces.
- Effective against fungi, vegetative bacteria, Mycobacterium species and some lipid-containing viruses.
- Not effective against spores.
- Most effective at 70% in water.
- May swell rubber or harden plastics.
- Do not use near flames due to flammability.
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IodineIodine vapour is highly toxic and is absorbed through the skin
Iodine is used in aqueous or alcoholic solution.
- Rapidly effective against most microorganisms.
- Usually diluted to 1% w/v free iodine, optimum pH neutral to acid.
- Not suitable in the presence of organic matter.
- Stains skin and may cause irritation.
- Dilute in alcohol for washing hands, or use as a sporicide.
- Prepare dilutions daily.
- Most commonly used for skin disinfection and decontaminating clean surfaces.
- Decomposes when heated above 40ºC.
- Do not use on aluminum or copper.
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FormaldehydePrecautions are required when handling formaldehyde (refer Australian Standard 2508.6.026)
Formalin is 37% w/v formaldehyde gas in water.
- Active against most microorganisms.
- 13% v/v formalin is a good decontaminant (but has an irritating odour).
- 8% v/v formalin in 80% v/v alcohol is effective against vegetative bacteria, spores and viruses.
- Does not corrode stainless steel.
- Use to disinfect equipment such as centrifuges or biosafety cabinets.
- Formaldehyde can be used to disinfect rooms, cubicles and safety cabinets: THIS PROCEDURE MUST BE PERFORMED BY NATA ACCREDITED PERSONNEL ONLY.
- Generated by heating paraformaldehyde suspended in silicone oil to 160ºC.
- Use 5 grams formaldehyde per cubic metre of space to be decontaminated.
- Requires relative humidity between 70% and 90% (humidity can be raised by evaporating water into the room).
- Formaldehyde can react with free chlorine to produce toxic gas. Remove hypochlorite solutions and hydrochloric acid from spaces to be decontaminated.
- Neutralise with ammonia following decontamination.
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GlutaraldehydeGlutaraldehyde is known to cause dermatitis and asthma
Glutaraldehyde is commercially available as 2% w/v aqueous solution which must be made alkaline to "activate" (e.g. by addition of 0.3% sodium bicarbonate).
- Active against vegetative bacteria, spores, fungi and many viruses.
- Less irritating than formaldehyde, but may cause dermatitis. Wear protective gloves when handling materials which have been immersed in glutaraldehyde.
- Discard if turbid.
- Also available in stable glycocomplexed form which does not require addition of alkaline buffer.
Chlorhexidine as chlorhexidine gluconate is dissolved in 70% alcohol.
- Use as antiseptic. Apply alcoholic chlorhexidine to the skin in the event of accidental contamination.
- Effective against Gram-positive organisms and HIV.
- Not recommended as a general disinfectant.
- Not active against sporulating bacteria or non-lipid-containing viruses.
- Active in pH range 5.5 - 8.0.
- Incompatible with soap and anionic detergents.
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Hydrogen PeroxideA concentration of 3% w/v generally used for disinfection.
- Active against a range of microorganisms.
- Fungi, spores and enteric viruses require higher concentration.
- No toxic end-products of decomposition.
- Do not use on aluminum, copper, zinc or brass.
Synthetic phenolics (clear soluble fluids) can be used as general disinfectants in the laboratory.
- Active against bacteria and lipid-containing viruses.
- Not active against spores and non-lipid-containing viruses.
- Active in presence of organic matter.
- Use for disinfecting floors, walls, benches and other furniture.
Quaternary ammonium compounds are positively charged (cationic) surface-active disinfectants.
- Effective against Gram-positive bacteria and lipid-containing viruses.
- Not recommended as general disinfectants (they have a narrow antibacterial spectrum).
- Inactivated by proteins, soap and anionic detergents.
The formation of life on earth has little to do with evolutionary sciences, which deal how lifechanges, not how it begins. The formation of life has as little to do, specifically, with evolution as it does with cell theory, or biogeography, or diet of organisms, or photosynthesis... it's a prerequisite for these processes.
What are the foods that cotain substances needed for building body cells?
Foods containing proteins, essential fatty acids, vitamins (such as vitamin C and vitamin D), and minerals (like iron and calcium) are crucial for building body cells. Foods like lean meats, fish, eggs, nuts, seeds, fruits, vegetables, and dairy products provide these important nutrients for cell growth and repair.
