All categories

3 years ago

Arunner sprints 550 feet in 100 seconds. If the runner can hold this pace for an hour

Chemistry

1 answer:

Alex3 years ago

6 0

<h3>Answer:</h3>

Distance traveled is 9.055 km

<h3>Explanation:</h3>

Speed is given by dividing distance by time.

The distance given is 550 ft and the time is 100 seconds.

Therefore; Speed = 550 ft ÷ 100 sec

= 5.5 ft/sec

We can calculate the distance the runner covered in one and half hour.

Time = 1.5 hours

But 1 hour = 3600 sec

1.5 hours = (1.5 × 3600)

= 5400 sec

Distance is given by multiplying speed and time

Thus; Distance = 5.5 ft/sec × 5400 sec

= 29700 ft

But; 1 m = 3.28 ft

1000 m = 1 km

Therefore; 29700 ft will be equivalent to

= 29700 ft/3.28 ft

= 9054.878 M

but 1000 m = 1 km

Thus, distance = 9054.878 ÷ 1000 m

= 9.055 km

You might be interested in

How many moles of H2 will be produced from 100 moles of water?2 H2O → 2 H2 + O2

ki77a [65]

In order to answer this question, we are going to look at the molar ratio between H2O and H2, we can see that by analyzing the numbers in front of the compounds, and we can see that the molar ratio is 2:2, this means that for every 2 moles of water decomposing, we will end up with 2 moles of H2 being produced, therefore the same amount of moles for H2O will be the same amount of moles of H2, which means that if we have 100 moles of H2O being decomposed, we will also have 100 moles of H2 being produced.

7 0

1 year ago

Be sure to answer all parts. What is the [H3O+] and the pH of a buffer that consists of 0.26 M HNO2 and 0.89 M KNO2? (K, of HNO2

Aleksandr-060686 [28]

Answer : The $H_3O^+$ ion concentration is, $1.12\times 10^{-3}M$ and the pH of a buffer is, 2.95

Explanation : Given,

$K_a=7.1\times 10^{-4}$

Concentration of $HNO_2$ (weak acid)= 0.26 M

Concentration of $KNO_2$ (conjugate base or salt)= 0.89 M

First we have to calculate the value of $pK_a$ .

The expression used for the calculation of $pK_a$ is,

$pK_a=-\log (K_a)$

Now put the value of $K_a$ in this expression, we get:

$pK_a=-\log (7.1\times 10^{-4})$

$pK_a=4-\log (7.1)$

$pK_a=3.15$

Now we have to calculate the pH of the solution.

Using Henderson Hesselbach equation :

$pH=pK_a+\log \frac{[Salt]}{[Acid]}$

$pH=pK_a+\log \frac{[KNO_2]}{[HNO_2]}$

Now put all the given values in this expression, we get:

$pH=3.15+\log (\frac{0.89}{0.26})$

$pH=2.95$

The pH of a buffer is, 2.95

Now we have to calculate the $H_3O^+$ ion concentration.

$pH=-\log [H_3O^+]$

$2.95=-\log [H_3O^+]$

$[H_3O^+]=1.12\times 10^{-3}M$

The $H_3O^+$ ion concentration is, $1.12\times 10^{-3}M$

4 0

3 years ago

Why do we use scientific notation or scientific exponential numbers in math calculations?

seraphim [82]

I believe the answer is: in order not to write very big or very small number values

6 0

3 years ago

What is the predominant intermolecular force in CBr4

vovikov84 [41]

CBr4 is a symmetric tetrahedral molecule so it will be non-polar.

3 0

3 years ago

Does gas have a definite denisty?

sergeinik [125]

Answer:

Explanation:

<h2><u><em>the particles in gas move so freely that it cannot have a definite density</em></u></h2><h2><u><em></em></u></h2><h2><u><em></em></u></h2><h2><u><em></em></u></h2><h2><u><em>moo</em></u></h2>

7 0

3 years ago