| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.02 |
| Score | 0% | 60% |
Which of these is matter than cannot be separated into different types of matter by ordinary chemical methods?
atom |
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molecule |
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compound |
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element |
An element is matter than cannot be separated into different types of matter by ordinary chemical methods.
Velocity is the rate at which an object changes position. What is the formula for velocity?
\(\vec{v} = { \vec{d} \over t } \) |
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\(\vec{v} = \vec{d}t \) |
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none of these |
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\(\vec{v} = { t \over \vec{d} } \) |
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 \(\vec{v} = { \vec{d} \over t } \)
Convert 5C° to F°.
37 |
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41 |
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-23 |
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27 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(5) + 32\)
\(F° = {45 \over 5} + 32\)
\(F° = 9 + 32 = 41\)
pH is a scale that measures of how basic or acidic a solution is. A solution with a pH of 9 is:
alkaline |
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water |
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acidic |
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neutral |
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.
As part of digestion, the liver produces bile which breaks down:
starches |
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fat |
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sugars |
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protein |
The liver produces bile which emulsifies (separates) fat.