| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.16 |
| Score | 0% | 63% |
Which of the following substances gives up positively charged hydrogen ions (H+) when dissolved in water?
solution |
|
base |
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acid |
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alkaline |
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.
Water coming to a boil on a stove, ice melting, and steam from a cup of coffee are all examples of which of the following?
radiation |
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convection |
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reflection |
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conduction |
Convection is the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.
Molecules and atoms that are outputs from a chemical reaction are known as which of the following?
reactants |
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results |
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products |
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side effects |
During a chemical reaction molecules and atoms (reactants) are rearranged into new combinations that result in new kinds of atoms or molecules (products).
Heat is always transferred from __________ to __________ environments.
cooler, warmer |
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warmer, cooler |
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empty, dense |
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dense, empty |
Heat is always transferred from warmer to cooler environments and conduction is the simplest way this transfer can occur. It is accomplished through direct contact between materials and materials like metals that transfer heat efficiently are called conductors while those that conduct heat poorly, such as plastic, are called insulators.
What part of the brain is responsible for for balance, movement, and muscle coordination?
medulla |
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cerebellum |
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brainstem |
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cerebrum |
The cerebellum is a large cluster of nerves at the base of the brain that's responsible for balance, movement, and muscle coordination.