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3 years ago

Do this Q7 if someone do I will her or him brainliest

Chemistry

1 answer:

spayn [35]3 years ago

6 0

The average speed :

1. 10.44 m/s

2. 10.42 m/s

3. 9.26 m/s

The distance 100 m have the greatest average speed

<h3>Further explanation</h3>

Given

Distance and time of runner

Required

Average speed

Solution

<em>Average speed : total distance : taotal time</em>

1. d = 100 m, t = 9.58 s

Average speed : 100 : 9.58 = 10.44 m/s

2. d=200 m, t=19.19 s

Average speed : 200 : 19.19 = 10.42 m/s

3. d=400 m, t = 43.18 s

Average speed : 400 : 43.18 = 9.26 m/s

The distance 100 m have the greatest average speed

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What is the molecular formula of a compound whose molar mass is 88.0 and whose percent composition is 54.5% carbon, 9.1% hydroge

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Answer:

C4H8O2

Explanation:

The molar mass of the compound we're looking for is 88.

54.5% of 88 is 4, this is how many carbons will be in the compound.

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and 36.4% of 88 is roughly 3, however if you subtract the previous amounts to round down, you get 2; the oxygen amount.

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3 years ago

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Answer:

The volume of ethylene glycol, we must add is 8.2 L

Explanation:

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ΔT = Kf . m . i

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In conclusion, we have 11000 g of water.

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