Answer the following question given this paragraph: Because energy is a product, energy is given off by the reaction. Therefore, this reaction is exothermic. Because energy is a reactant, energy is absorbed by the reaction. Therefore, this reaction is endothermic. Q: In an endothermic reaction, what is absorbed by the reaction? Choices: - food - fuel - atoms - energy A:
energy
Answer the following question given this paragraph: 12.7 Molecular Transport Phenomena: Diffusion, Osmosis, and Related Processes 62. You can smell perfume very shortly after opening the bottle. To show that it is not reaching your nose by diffusion, calculate the average distance a perfume molecule moves in one second in air, given its diffusion constant D to be 1.0010 6 m 2 /s . What is the ratio of the average distances that oxygen will diffuse in a given time in air and water? Why is this distance less in water (equivalently, why is D less in water)? 64. Oxygen reaches the veinless cornea of the eye by diffusing through its tear layer, which is 0.500-mm thick. How long does it take the average oxygen molecule to do this? 65. (a) Find the average time required for an oxygen molecule to diffuse through a 0.200-mm-thick tear layer on the cornea. 3 (b) How much time is required to diffuse 0.500 cm of oxygen to the cornea if its surface area is 1.00 cm 2 ? 66. Suppose hydrogen and oxygen are diffusing through air. A small amount of each is released simultaneously. How much time passes before the hydrogen is 1.00 s ahead of the oxygen? Such differences in arrival times are used as an analytical tool in gas chromatography. Q: Oxygen reaches what veinless part of the eye by diffusing through its tear layer? Choices: - retina - pupil - membranes - cornea A:
cornea
Q: Answer the following question given this paragraph: During World War II, battleships and submarines carried echo sounders. Their goal was to locate enemy submarines ( Figure below ). Echo sounders produce sound waves that travel outward in all directions. The sound waves bounce off the nearest object and then return to the ship. Scientists know the speed of sound in seawater. They then can calculate the distance to the object that the sound wave hit. Most of these sound waves did not hit submarines. They instead were used to map the ocean floor. Q: What produces sound waves that travel outward in all directions in water? Choices: - echo chamber - ultrasound machines - amplifiers - echo sounders A:
A: echo sounders
Question: Answer the following question given this paragraph: Earth itself acts like a gigantic gyroscope. Its angular momentum is along its axis and points at Polaris, the North Star. But Earth is slowly precessing (once in about 26,000 years) due to the torque of the Sun and the Moon on its nonspherical shape. Q: Earth acts like a giant version of what device, with angular momentum along its axis and pointing at polaris, the north star? Choices: - compass - telescope - accelerator - gyroscope A:
Answer: gyroscope
*Question*
Answer the following question given this paragraph: Clouds form when water vapor condenses in the air around specs of matter. Clouds are classified on the basis of where and how they form. Types of clouds include cirrus, stratus, and cumulus clouds. Q: What form when water vapor condenses in the air around specs of matter? Choices: - humidity - storms - condensation - clouds A:
**Answer**
clouds
(Q).
Answer the following question given this paragraph: Most of the energy used by living things comes either directly or indirectly from the sun. That's because sunlight provides the energy for photosynthesis. This is the process in which plants and certain other organisms synthesize glucose (C 6 H 12 O 6 ). The process uses carbon dioxide and water and also produces oxygen. The overall chemical equation for photosynthesis is:. Q: Most of the energy used by living things comes either directly or indirectly from what? Choices: - plants - the moon - the soil - the sun A:
(A).
the sun