| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.07 |
| Score | 0% | 61% |
Which of the following substances gives up positively charged hydrogen ions (H+) when dissolved in water?
solution |
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alkaline |
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base |
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acid |
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.
Minerals, vitamins, and fiber are:
macronutrients |
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proteins |
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micronutrients |
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carbohydrates |
Minterals, vitamins, and fiber are micronutrients while proteins, carbohydrates, and fats are macronutrients.
The rows of the Periodic Table of the Elements are called:
families |
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periods |
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shells |
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groups |
The rows of the Periodic Table are called periods and contain elements that have the same number of electron shells ordered from lower to higher atomic number.
The Sun is a __________-type main-sequence star.
G |
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S |
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D |
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E |
The Sun is a G-type main-sequence star (G2V) but is informally known as a yellow dwarf star. Composed of 73% hydrogen and 25% helium, the hot plasma that makes up the Sun reaches 9,900°F (5,505°C) at the surface. It formed approximately 4.6 billion years ago and makes up 99.86% of the mass in the solar system.
Elements in the same group in the Periodic Table of the Elements have the same:
number of electrons in their outer electron shell |
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number of atomic mass units |
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number of electrons |
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number of electron shells |
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.