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2 years ago

An athlete preparing for a marathon runs 21.3 miles. How many kilometers did they run?

Chemistry

1 answer:

densk [106]2 years ago

8 0

Answer: 34.27903 km

Explanation: for an approximate result, multiply the length value by 1.609 to 21.3 to get answer.

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Answer:

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2 years ago

What particles in an atom are involved in nuclear reactions

VikaD [51]

Answer:

Explanation:

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3 years ago

What is the percent composition by mass of sulfur in the compound MgSO4 (gram formula mass = 120 g/mol)?

slavikrds [6]

26.7% is the percent composition by mass of sulfur in a compound named magnesium sulfate. Explanation: Molar mass of compound = 120 g/mol.

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2 years ago

500 mL of water is added to 400 mL of 0.35 M HCl. Find the concentration of the diluted solution.

jarptica [38.1K]

The concentration of diluted solution is 0.16 M

<u>Explanation:</u>

As, the number of moles of diluted solution and concentrated solution will be same.

So, the equation used to calculate concentration will be:

$M_1V_1=M_2V_2$

where,

$M_1\text{ and }V_1$ are the molarity and volume of the concentrated HCl solution

$M_2\text{ and }V_2$ are the molarity and volume of diluted HCl solution

We are given:

$M_1=0.35M\\V_1=400mL\\M_2=?M\\V_2=(500+400)mL=900mL$

Putting values in above equation, we get:

$0.35\times 400=M_2\times 900\\\\M_2=\frac{0.35\times 400}{900}=0.16M$

Hence, the concentration of diluted solution is 0.16 M

5 0

3 years ago

If the cylindrical pistons are 25.000 cm in diameter at 20.0 ∘c, what should be the minimum diameter of the cylinders at that te

attashe74 [19]

Refer to the diagram shown below.

The piston supports the same load W at both temperatures.
The ideal gas law is
$pV=nRT$
where
p = pressure
V = volume
n = moles
T = temperature
R = gas constant

State 1:
T₁ = 20 C = 20+273 = 293 K
d₁ = 25 cm piston diameter

State 2:
T₂ = 150 C = 423 K
d₂ = piston diameter

Because V, n, and R remain the same between the two temperatures, therefore
$\frac{p_{1}}{T_{1}} = \frac{p_{2}}{T_{2}}$

If the supported load is W kg, then
$p_{1} = \frac{W \, N}{ \frac{\pi}{4} d_{1}^{2}} = \frac{4W \, N}{\pi (0.25 \, m)^{2}} = 20.3718W \, Pa$
Similarly,
$p_{2} = \frac{4W}{\pi d_{2}^{2}} \, Pa$

$\frac{p_{1}}{p_{2}} = \frac{20.3718 \pi d_{2}^{2}}{4} = 16 d_{2}^{2}$

Because p₁/p₂ = T₁/T₂, therefore
$16d_{2}^{2} = \frac{293}{423} \\\\ d_{2}^{2} = \frac{0.6927}{16} \\\\ d_{2} = 0.2081 \, m$

The minimum piston diameter at 150 C is 20.8 cm.

Answer: 20.8 cm diameter

8 0

3 years ago