[Q]: Given the background: Liquid water is a fluid. The hydrogen bonds in liquid water constantly break and reform as the water molecules tumble past one another. As water cools, its molecular motion slows and the molecules move gradually closer to one another. The density of any liquid increases as its temperature decreases. For most liquids, this continues as the liquid freezes and the solid state is denser than the liquid state. However, water behaves differently. It actually reaches its highest density at about 4C. and the situation: Joe is at a party and carrying around a can of beer that he has had in his hand for awhile. He bumps into Sally, and they begin chatting. During their conversation, Sally notices the beer in Joe's hand, and remarks that a beer sounds like a good idea. She heads over to the refrigerator and grabs a nice cold one and pops it open. She takes a sip while the two continue their chat. Answer the following question: The molecules in whose can of beer are moving slower?
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[A]: Sally

[Q]: Given the background: A catalyst is a substance that increases the rate of a chemical reaction. A catalyst is a substance that increases the rate of a chemical reaction. The presence of a catalyst is one of several factors that influence the rate of chemical reactions. (Other factors include the temperature, concentration, and surface area of reactants.) A catalyst isn't a reactant in the chemical reaction it speeds up. As a result, it isn't changed or used up in the reaction, so it can go on to catalyze many more reactions. and the situation: Henry and Tiffany are performing chemical reactions in their high school chemistry class. Henry performs his reactions with the use of a catalyst. Tiffany performs the same reaction with no catalyst present. Answer the following question: Which person's reactions will occur at a faster rate?
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[A]: Henry

[Q]: Given the background: When the temperature of reactants is higher, the rate of the reaction is faster. At higher temperatures, particles of reactants have more energy, so they move faster. They are more likely to bump into one another and to collide with greater force. For example, when you fry an egg, turning up the heat causes the egg to cook faster. The same principle explains why storing food in a cold refrigerator reduces the rate at which food spoils (see Figure below ). Both food frying and food spoiling are chemical reactions that happen faster at higher temperatures. and the situation: John just opened a coffee shop. He offers two types of coffee, coffee A and coffee B. In coffee A he mixes ingredients in hot water, but in coffee B he mixes ingredients in cold water. He also notices that his shop gets very busy in the morning, but during evening he doesn't have many customers. Answer the following question: Would coffee A be faster or slower to make than coffee B?
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[A]: faster

[Q]: Given the background: For most substances, when the temperature of the solid is raised high enough, the substance changes to a liquid, and when the temperature of the liquid is raised high enough, the substance changes to a gas. We typically visualize a solid as tiny particles in constant motion held together by attractive forces. As we add heat to the solid, the motion, or the kinetic energy, of the particles increases. At some temperature, the motion of the particles becomes great enough to overcome the attractive forces. The thermal energy that was added to the solid up to this point was absorbed by the solid as kinetic energy, increasing the speed of the molecules. The lowest temperature at which the particles are able to exist in the liquid form is called the melting point . and the situation: As a science experiment for his school homework, Kendra is putting two ice cubes on separate pans and then putting those pans on burners set to different temperatures. Ice cube A is set on top of a burner set to a low temperature, and ice cube B is placed on a burner set quite a bite higher. One minute later, Kendra begins writing down what she sees happening to the ice cubes. Answer the following question: Which ice cube will melt slower?
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[A]:
Ice cube A