| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.26 |
| Score | 0% | 65% |
A subatomic particle found in the nucleus of an atom. It carries a positive electric charge. This desribes which of the following?
atom |
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proton |
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neutron |
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electron |
A proton is a subatomic particle found in the nucleus of an atom. It carries a positive electric charge.
In the Periodic Table of the Elements, atomic number is equal to which of the following?
number of neutrons in the nucleus |
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number of protons + neutrons in the nucleus |
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number of protons in the nucleus |
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number of electrons orbiting the nucleus |
The Periodic Table of the Elements categorizes elements primarily by the number of protons in their nucleus (atomic number) and secondarily by the characteristics they exhibit.
Velocity is the rate at which an object changes position. What is the formula for velocity?
\(\vec{v} = \vec{d}t \) |
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\(\vec{v} = { t \over \vec{d} } \) |
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none of these |
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\(\vec{v} = { \vec{d} \over t } \) |
Velocity is the rate at which an object changes position. Rate is measured in time and position is measured in displacement so the formula for velocity becomes \(\vec{v} = { \vec{d} \over t } \)
The coldest point in the Earth's atmosphere is reached in which atmospheric layer?
mesosphere |
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thermosphere |
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stratosphere |
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troposphere |
In the mesosphere, temperature again drops as altitude increases until the coldest point in the Earth's atmosphere, the mesopause, is reached where temperatures fall to −225 °F (−143 °C).
Plant cells are surrounded by:
a cell membrane and a cell wall |
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only a cell membrane |
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only a cell wall |
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neither a cell membrane nor a cell wall |
Animal cells are surrounded by a semipermeable membrane which allows for the transfer of water and oxygen to and from the cell. In plant cells, the cell membrane is surrounded by a somewhat rigid cell wall which provides the cell structure and support.