Q: Answer the following question given this paragraph: Because isomers are different compounds, they have different properties. Generally, branched-chain isomers have lower boiling and melting points than straight-chain isomers. For example, the boiling and melting points of iso -butane are -12 C and -160 C, respectively, compared with 0 C and -138 C for n -butane. The more branching there is, the lower the boiling and melting points are. Q: Which type of isomers generally have lower boiling and melting points than straight-chain isomers? Choices: - straight-chain isomers - branched-looping isomers - branched - solar isomers - branched-chain isomers A:
A: branched-chain isomers

Q: Answer the following question given this paragraph: The Tyndall effect is the scattering of visible light by colloidal particles. Q: The tyndall effect refers to the scattering of what by colloidal particles? Choices: - primary colors - dark matter - dust mites - visible light A:
A: visible light

Q: Answer the following question given this paragraph: The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table below . Q: What is the major cause of outdoor air pollution? Choices: - electric lines - agricultural equipment - manufacturing industry - burning fossil fuels A:
A: burning fossil fuels

Q: Answer the following question given this paragraph: Sodium is a highly reactive metal, and chlorine is a poisonous gas (see Figure below ). The compound they synthesize has very different properties. It is table salt, which is neither reactive nor poisonous. In fact, salt is a necessary component of the human diet. Q: Sodium and chlorine combine to make what? Choices: - gold - seawater - iron - salt A:
A: salt