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When a chemical reaction absorbs or releases thermal energy, the reaction causes a change in temperature. Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
Airbags reduce injuries during car crashes by inflating quickly to provide cushions for people inside a car. Older airbags contain a small amount of sodium azide (NaN3). If a crash occurs, the sodium azide is heated, causing it to break down into sodium metal (Na) and nitrogen gas (N2). In less than one-tenth of a second, enough nitrogen gas is produced to completely fill the airbag. As a result of the reaction, thermal energy is transferred into the surroundings.
Complete the statement.
During this chemical reaction, the airbag becomes __________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
To clean their drain pipes, some people make a solution of baking soda and vinegar. Baking soda, also known as sodium bicarbonate (NaHCO3), reacts with acetic acid (C2H4O2) in vinegar to produce sodium acetate (NaC2H3O2), water (H2O), and carbon dioxide gas (CO2). As the products form, thermal energy is absorbed from the surroundings and converted to chemical energy. The carbon dioxide gas creates bubbles that help clean the inside of the pipes.
Complete the statement.
During this chemical reaction, the solution becomes _________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
The gasoline used in cars today is a mixture of over 1,000 different substances. One of these substances is isooctane (C8H18). In a car engine, isooctane reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). During the reaction, a large amount of thermal energy is released into the surroundings. This thermal energy is used to power the car.
Complete the statement.
During a chemical reaction, the car engine becomes _________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
The most common type of cement in the world is Portland cement, named after an area of England that has a lot of limestone. Limestone is made up mostly of calcium carbonate (CaCO3). When calcium carbonate is heated, it breaks down into carbon dioxide (CO2) and calcium oxide (CaO), the main ingredient in Portland cement. During this reaction, thermal energy is taken in from the surroundings and converted to chemical energy.
Complete the statement.
During a chemical reaction, the air around the reaction becomes _________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
Dynamite contains the compound nitroglycerin (C3H5N3O9). When dynamite is lit, the nitroglycerin explodes, forming nitrogen (N2), carbon monoxide (CO), water (H2O), and oxygen (O2). This reaction quickly releases a huge amount of thermal energy into the surroundings. Because so much energy is released in such a short time, dynamite can be used to blast through solid rock.
Complete the statement.
During the chemical reaction, the air around the reaction becomes ________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
Sal ammoniac, a rare mineral made up of ammonium chloride (NH4Cl), is usually found near the vents of active volcanos. To collect samples of sal ammoniac, geologists must work when the weather is dry. If rainwater falls on the sal ammoniac, the mineral quickly dissolves to form a solution of ammonium ions (NH4+) and chloride ions (Cl?). The process of forming the ions absorbs thermal energy from the surroundings and converts it to chemical energy.
Complete the statement.
During the chemical reaction, the solution becomes _________ .
Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
An antacid is a medicine used to calm an upset stomach. Antacid tablets contain a mixture of sodium bicarbonate (NaHCO3) and citric acid (C6H8O7). When a tablet is dissolved in water, these substances react to form sodium citrate (Na3C6H5O7), water (H2O), and carbon dioxide (CO2) in the solution. During the reaction, thermal energy is absorbed from the surroundings. When a person swallows this antacid solution, the sodium citrate can help relieve stomach pain.
Complete the statement.
During the chemical reaction, the solution becomes ________ .
Read the passage about a chemical reaction that causes a change in temperature. Then, follow the instructions below.
An athlete can apply an instant cold pack after an injury to help reduce swelling. An instant cold pack is a small bag containing two pouches, one filled with water and the other filled with ammonium nitrate (NH4NO3). The athlete activates the pack by squeezing the bag to break the pouches open, allowing the water and ammonium nitrate to mix. When this happens, the ammonium nitrate dissolves in the water, forming ammonium ions (NH4+) and nitrate ions (NO3?), and the pack becomes cold.
Select the true statement.
Read the passage about a chemical reaction that causes a change in temperature. Then, follow the instructions below.
The most common type of cement in the world is Portland cement, named after an area of England that has a lot of limestone. Limestone is made up mostly of calcium carbonate (CaCO3). When calcium carbonate is heated, it breaks down into carbon dioxide (CO2) and calcium oxide (CaO), the main ingredient in Portland cement. As the products form, the air around the reaction becomes cooler.
Select the true statement.
Read the passage about a chemical reaction that causes a change in temperature. Then, follow the instructions below.
Some people use disposable hand warmers to stay comfortable on cold days. A hand warmer is a small pouch that contains powdered iron (Fe), as well as salt and water. When the hand warmer is removed from its packaging, oxygen gas (O2) drifts through small holes in the material of the pouch. In the presence of the salt and water, the oxygen quickly reacts with the iron powder to form ferric oxide (Fe2O3). As the reaction occurs, the temperature of the pouch increases.
Select the true statement.