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2 years ago

9

On a recent car ride, a student traveled the first 20 kilometers in 5 minutes, the next 60 kilometers in 50 minutes, and the las

t 10 kilometers in 5 minutes. What was the average speed of the car over the student's entire ride?
1.5 km/min

5 km/min

2 km/min

4 km/min

1 answer:

inn [45]2 years ago

6 0

Answer:

it is 90 km in one hour it is 90km/h

90/60=1,5

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2 years ago

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Answer:

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Explanation:

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Mass of CO₂ obtained = 53.0 grams

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Now,

the molar mass of the calcium carbonate = 100.08 grams

The number of moles heated in the problem = Mass / Molar mass

= (1.31 grams) / (100.08 grams/moles)

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now,

1 mol of calcium carbonate yields 1 mol of CO₂

thus,

0.013088 moles of calcium carbonate will yield = 0.013088 mol of CO₂

now,

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or

the percent yield for this reaction = $\frac{0.53}{0.5758}\times100$

or

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