Q: A large log placed in a fire will burn relatively slowly. If the same mass of wood were added to the fire in the form of small twigs, they would burn much more quickly. This is because the twigs provide a greater surface area than the log does. An increase in the surface area of a reactant increases the rate of a reaction. Surface area is larger when a given amount of a solid is present as smaller particles. A powdered reactant has a greater surface area than the same reactant as a solid chunk. In order to increase the surface area of a substance, it may be ground into smaller particles or dissolved into a liquid. In solution, the dissolved particles are separated from each other and will react more quickly with other reactants. Two friends went camping and made a fire each. Bill used a few large logs while Tim used kindlings, wood chips and sawdust. they both brought the same volume of wood. Which friend provided a smaller wood surface area for the fire to burn?
A: Bill

Q: One result of air pollution is acid rain. Acid rain is precipitation with a low (acidic) pH. This rain can be very destructive to wildlife. When acid rain falls in forests, freshwater habitats, or soils, it can kill insects and aquatic life. It causes this damage because of its very low pH. Sulfur oxides and nitrogen oxides in the air both cause acid rain to form ( Figure below ). Sulfur oxides are chemicals that are released from coal-fired power plants. Nitrogen oxides are released from motor vehicle exhaust. The ecologist moved from Aspen, where there was no air pollution, to Seattle which experienced a lot of air pollution. He started studying the weather there as well. Which city had more sulfur oxides in the air?
A: Seattle

Q: One reason radiation is dangerous is that it can't be detected with the senses. You normally can't see it, smell it, hear it, or feel it. Fortunately, there are devices such as Geiger counters that can detect radiation. A Geiger counter, like the one in Figure below , has a tube that contains atoms of a gas. If radiation enters the tube, it turns gas atoms to ions that carry electric current. The current causes the Geiger counter to click. The faster the clicks occur, the higher the level of radiation. David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation. In which city the gas inside a Geiger counter would be ionized, Hiroshima or Tokyo?
A: Hiroshima

Q: Ocean acidification occurs when excess carbon dioxide in the atmosphere causes the oceans to become acidic. Burning fossil fuels has led to an increase in carbon dioxide in the atmosphere. This carbon dioxide is then absorbed by the oceans, which lowers the pH of the water. Ocean acidification can kill corals and shellfish. It may also cause marine organisms to reproduce less, which could harm other organisms in the food chain. As a result, there also may be fewer marine organisms for humans to consume. The biologists found out that the Indian Ocean had a lower water pH than it did a decade ago, and it became acidic. The water in the Arctic ocean still had a neutral to basic pH. Which ocean lost fewer corals because of its acidity?
A:
Arctic