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3 years ago

Why must the retina be smooth in a living eye

1 answer:

6 0

The cornea does not contain any blood vessels, but instead contains many nerve endings that make it extremely sensitive. That is why a scratch or a loose eyelash is so painful.

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One of the main components of an airbag is the gas that fills it. As part of the design process, you need to determine the exact

alekssr [168]

Answer:

One of the main components of an airbag is the gas that fills it. As part of the design process, you need to determine the exact amount of nitrogen that should be produced. Calculate the number of moles of nitrogen required to fill the airbag. Show your work. Assume that the nitrogen produced by the chemical reaction is at a temperature of 495°C and that nitrogen gas behaves like an ideal gas. Use this fact sheet to review the ideal gas law.

6 0

3 years ago

Read 2 more answers

HELP WITH CHEMISTRY PLEASE!

maria [59]

Answer:

1) 1.52 atm.

2) 647.85 K.

3) 20.56 L.

4) 1.513 mole.

5) 254.22 K = -18.77 °C.

Explanation:

In all this points, we should use the law of ideal gas to solve this problem: PV = nRT.
Where, P is the pressure (atm), V is the volume (L), n is the number of moles, R is the general gas constant (0.082 L.atm/mol.K), and T is the temperature (K).

1) In this point; n, R, and T are constants and the variables are P and V.

P and V are inversely proportional to each other that if we have two cases we get: P1V1 = P2V2.

In our problem:

P1 = ??? (is needed to be calculated) and V1 = 45.0 L.

P2 = 5.7 atm and V2 = 12.0 L.

Then, the original pressure (P1) = P2V2 / V1 = (5.7 atm x 12.0 L) / (45.0 L) = 1.52 atm.

2) In this case, n and R are the constants and the variables are P, V, and T.

P and V are inversely proportional to each other and both of them are directly proportional to the temperature of the gas that if we have two cases we get: P1V1T2 = P2V2T1.

In our problem:

P1 = 212.0 kPa, V1 = 32.0 L, and T1 = 20.0 °C = (20 °C + 273) = 293 K.

P2 = 300.0 kPa, V2= 50.0 L, and T2 = ??? (is needed to be calculated)

Then, the temperature in the second case (T2) = P2V2T1 / P1V1 = (300.0 kPa x 50.0 L x 293 K) / (212.0 kPa x 32.0 L) = 647.85 K.

3) In this case, P, n and R are the constants and the variables are V, and T.

V and T are directly proportional to each other that if we have two cases we get: V1T2 = V2T1.

In our problem:

V1 = 25.0 L and T1 = 65.0 °C + 273 = 338 K.

V2 = ??? (is needed to be calculated) and T2 = 5.0 °C + 273 = 278 K.

Herein, there is no necessary to convert T into K.

Then, the volume in the second case (V2) = V1T2 / T1 = (25.0 L x 278 °C) / (338 °C) = 20.56 L.

4) We can get the number of moles that will fill the container from: n = PV/RT.

P = 250.0 kPa, we must convert the unit from kPa to atm; 101.325 kPa = 1.0 atm, then P = (1.0 atm x 250.0 kPa) / (101.325 kPa) = 2.467 atm.

V = 16.0 L.

R = 0.082 L.atm/mol.K.

T = 45 °C + 273 = 318 K.

Now, n = PV/RT = (2.467 atm x 16.0 L) / (0.082 L.atm/mol.K x 318 K) = 1.513 mole.

5) In this case, V, n and R are the constants and the variables are P, and T.

P and T are directly proportional to each other that if we have two cases we get: P1T2 = P2T1.

In our problem:

P1 = 2200.0 mmHg and T1 = ??? (is needed to be calculated) .

P2 = 2700.0 mmHg and T2 = 39.0 °C + 273 = 312.0 K.

Herein, there is no necessary to convert P into atm.

Then, the temperature in the morning (T1) = P1T2 / P2 = (2200.0 mmHg x 312.0 K) / (2700.0 mmHg) = 254.22 K = -18.77 °C.

6 0

3 years ago

Read 2 more answers

I give brainliest

Tatiana [17]

Answer: During winter the Northern Hemisphere leans away from the sun, there are fewer daylight hours and the sun hits us at an angle. This makes it appear lower in the sky. In equatorial regions the length of days and the directness of sunlight don't change as much.

Hope this helps :)

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3 years ago

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Which substance is an electrolyte? 1. O2 2. Xe 3. C3H8 4. KNO3

Troyanec [42]

KNO3 is an electrolyte

3 0

3 years ago

b. Determine the molecular formula of a molecule with an empirical formula NH2and a molar mass of 32 g/mol.

VladimirAG [237]

I'm taking this lesson now, so imma help u ( if u need anything else ask me)

so given Molar mass= 32 g/mol
molar mass= (empirical formula) n
32 = (14x1 + 2x1) n
32 = 16 n , so n= 2
so, molecular formula= N2H4

5 0

3 years ago