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3 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]3 years ago

6 0

Answer:

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

90/60=1,5

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C. As scientists have learned more about chemicals, they have become more aware of their dangers

Explanation:

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3 years ago

A sample was prepared by mixing 18. ml of 3.00 x 10^-3 m crystal violet (cv) with 2.00 ml of 0.250 m naoh. calculate the resulti

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Answer : The resulting concentrations of CV and NaOH are 0.0027 M and 0.025 M respectively.

Explanation :

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Molarity of crystal violet = $3.00 \times 10^{-3} = \frac{mol (CrystalViolet)}{L}$

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Moles of NaOH = 5.00 x 10⁻⁴

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The total volume of the solution after mixing NaOH and crystal violet is

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Step 3 : Use molarity formula to find final concentrations

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$NaOH (aq) \rightarrow Na^{+} (aq) + OH^{-} (aq)$

The mole ratio of NaOH and OH⁻ is 1:1 . Therefore the concentration of OH⁻ is same as that of NaOH.

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3 years ago

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calculation

molarity =moles of solute/ Kg of the solvent

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