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What happens after a substance goes through a chemical change?
Yes because when a chemical change happens the substance may not have some of the physical or chemical properties it had once before. An example of htis would be Dry Ice. This would be an example because dry ice was once just ice then they add a chemical and it turns into dry ice.
Is carbon dioxide and dry ice 2 different chemical of the same state?
Solid carbon dioxide is dry ice.
When a new substance is formed with different properties than the original substance is called what?
1) Any mixture of things typically has properties different than its components. Examples: a) Mixing pure elements to make a new chemical compound (e.g. Oxygen plus Carbon can combine to form CO2, which has properties different than either C or O. Carbon monoxide has different properties than CO2) b) Mixing chemicals - e.g., Hydrochloric Acid (HCl) plus Sodium Hydroxide (NaOH, aka. Lye) combines to form water H2O and ordinary salt (NaCl) c) Mixing metals forms an Alloy - e.g., Gold plus a little copper yields "red gold" which is harder than pure gold. Lead mixed with tin has a lower melting point than either metal. d) Agregates - Even a mixure of sand and water to create wet sand has properties (behaviors) different than the separate components (try building a sand castle with dry sand). Mixing paint produces a new color of paint. 2) Phase change Examples: a) Water has different properties when frozem, liquid or steam b) Solid CO2 (aka. Dry Ice) has different properties than gaseous CO2 3) Application of energy Examples a) Baking cake batter irreversibly changes the batter into something with different properties (yum!) Frying an egg causes an irreversible property change. b) Roasting limestone to remove the water of hydration is a important step in making Calcium oxide for use in creating Cement etc., etc., etc.
What chemical properties do ice and dry ice have in common?
Ice (solid water) exists only below 0oC. About dry ice (solid carbon dioxide, CO2) the following should be taken into account: At pressures below 5.13 atm and temperatures below −56.4 °C (−69.5 °F) (the so called triple point), CO2 changes from a solid to a gas with no intervening liquid form, through a process called sublimation (evaporation from solid state).
Why is the insulating properties of neoprene is not needed on a drysuit?
Neoprene is not typically used in drysuits for its insulating properties because drysuits are designed to keep the wearer dry, not warm. Neoprene wetsuits are used for insulation in cold water because they trap a thin layer of water against the skin that warms up to provide insulation. Drysuits use breathable waterproof materials to keep the wearer dry without the need for insulating properties.
What are the different types of fire etinguishers?
Water, carbon dioxide, and dry chemical.
What happens after a substance goes through a chemical change?
Yes because when a chemical change happens the substance may not have some of the physical or chemical properties it had once before. An example of htis would be Dry Ice. This would be an example because dry ice was once just ice then they add a chemical and it turns into dry ice.
What gas has the same chemical properties as dry ice?
Carbon Dioxide
What types of fire extinguishing equipment used for different categories of fire?
Using the American system for classification, here's the general type of extinguisher used:A (combustible materials) - water, AFFF (aqueous fire fighting film), dry chemicalB (flammable liquid or gas) - NEVER water. Dry chemical, AFFF, Halon, CO2C (electrical fires) - NEVER water. Dry chemical, Halon, CO2D (flammable metals) - NEVER water. Dry POWDER (not dry chemical) such as sodium chloride granules, graphite or copper.
How many kilograms of dry chemical must be added to 90l of water to produce a o2 percent chemical solution?
To solve this problem, we first need to determine the total mass of the solution, which includes the water and the dry chemical. Since the density of water is 1 kg/l, 90 liters of water would weigh 90 kg. If the final solution is 2% dry chemical, then the dry chemical would weigh 2% of the total mass of the solution. Therefore, 2% of the total mass equals the mass of the dry chemical needed. So, the mass of the dry chemical required would be 0.02 * (90 kg + X kg), where X represents the mass of the dry chemical in kilograms.
Is a physical change A. an iron bar rusting B. oil floating on water C. a copper skillet tarnishing D. the sublimation of dry ice?
The answer is D; the sublimation of dry ice. A physical change alters one of the physical properties of a substance (e.g. size, shape, color, etc.), but it does not change the substance itself. A chemical change causes new substances to be formed. The new substances have different chemical properties from the original substance. Changes in the state or phase of matter, such as the sublimation of dry ice (solid carbon dioxide), are physical changes because the chemical compositions of the substances do not change. Sublimation is the change of an object from a solid-state directly to a gaseous state.
What to do if a dry chemical is on you?
It depends on the dry chemical. Sodium chloride is a dry chemical that you just have to wipe off. Sodium hydroxide is a dry chemical too, but if you get it on yourself you need to flush your skin with cold running water for 15 minutes then go to the emergency room. The answer to your question is found in the Material Safety Data Sheet for the chemical you are using.
Why is the sublimation of dry ice and the expansion of gases not chemical reations?
A chemical reaction is one that changes the chemical properties of a substance. Sublimation is just going from solid to a gas and is only a change of state.
Should a dry chemical extinguisher or a pressure water extinguisher be used on an electrical fire?
You would not want to use a pressure water extinguisher on any electrical fire due to the possibility of electricity being conducted through the water and injuring someone. A CO2, dry chemical or "clean agent" (e.g., "Halogenated") extinguisher would be a better choice for an electrical fire, knowing that dry chemical powder will make quite a mess.
Is carbon dioxide and dry ice 2 different chemical of the same state?
Solid carbon dioxide is dry ice.
Does the surface of the moon have water?
The moon isn't the dry dull place it seems. Traces of water lurk in the dirt unseen. Three different space probes found the chemical signature of water all over the moon's surface.
What is the correct substance to use in putting out an electrical fire?
With a dry chemical or CO2 fire extinguisher. Anything not conductive certainly not water.
