| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.95 |
| Score | 0% | 59% |
Convert 5C° to F°.
37 |
|
41 |
|
27 |
|
-23 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(5) + 32\)
\(F° = {45 \over 5} + 32\)
\(F° = 9 + 32 = 41\)
Which of the following is not a medium for sound waves?
liquid |
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solid |
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vacuum |
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none of these is a medium for sound waves |
A vibrating object produces a sound wave that travels outwardly from the object through a medium (any liquid or solid matter). The vibration disturbs the particles in the surrounding medium, those particles disturb the particules next to them, and so on, as the sound propagates away from the vibration.
Elements in the same group in the Periodic Table of the Elements have the same:
number of electron shells |
|
number of electrons |
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number of electrons in their outer electron shell |
|
number of atomic mass units |
The columns of the Periodic Table are called groups and all elements in a group have the same number of electrons in their outer electron shell. The group that an element occupies generally determines its chemical properties as the number of outer shell electrons establishes the way it reacts with other elements to form molecules. So, because each element has the same number of electrons in its outer shell, each has similar reactivity.
The hottest of Earth's atmospheric layers is which of the following?
mesosphere |
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thermosphere |
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stratosphere |
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troposphere |
Temperatures again increase with altitude in the thermosphere which is the hottest (4,530 °F / 2,500 °C) atmospheric layer due to direct exposure to the Sun's radiation. However, the gas in this layer is highly diluted so even though the atoms of gas may be very high in temperature, there are too few of them to effectively transfer much heat.
Molecules and atoms that are outputs from a chemical reaction are known as which of the following?
reactants |
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products |
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results |
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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).