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3 years ago

How does the sun's position in the sky affect rainbows?

1 answer:

3 0

When the sun is low in the sky, light rays pass horizontally through more of the lower atmosphere to reach the earth's surface or an observer's eye. ... Because short-wavelength blue and green light are scattered more than red and yellow light, rainbows at times of sunrise and sunset often display the brightest reds.

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An ideal gas in a cylindrical container of radius r and height h is kept at constant pressure p. The bottom of the container is

Juli2301 [7.4K]

Answer:

$m =\frac{p*(pi)*r^{2}*h*mw}{R*\frac{T_{1} + T_{O}}{2}}$

Explanation:

The gas ideal law is

PV= nRT (equation 1)

Where:

P = pressure

R = gas constant

T = temperature

n= moles of substance

V = volume

Working with equation 1 we can get

$n =\frac{PV}{RT}$

The number of moles is mass (m) / molecular weight (mw). Replacing this value in the equation we get.

$\frac{m}{mw} =\frac{PV}{RT}$ or

$m =\frac{P*V*mw}{R*T}$ (equation 2)

The cylindrical container has a constant pressure p

The volume is the volume of a cylinder this is

$V =(pi)*r^{2}*h$

Where:

r = radius

h = height

(pi) = number pi (3.1415)

This cylinder has a radius, r and height, h so the volume is $V =(pi)*r^{2}*h$

Since the temperatures has linear distribution, we can say that the temperature in the cylinder is the average between the temperature in the top and in the bottom of the cylinder. This is:

$T =\frac{T_{1} + T_{O}}{2}$

Replacing these values in the equation 2 we get:

$m =\frac{P*V*mw}{R*T}$ (equation 2)

$m =\frac{p*(pi)*r^{2}*h*mw}{R*\frac{T_{1} + T_{O}}{2}}$

8 0

3 years ago

How is a joule defined?

andreyandreev [35.5K]

Answer:

A. It is the work done when a force of 1 newton is applied to an object for a distance of 1 meter

Explanation:

5 0

3 years ago

A gas is contained in a cylinder with a volume of 2.9 L at a temperature of 32.7oC and a pressure of 645.3 torr. The gas is then

stealth61 [152]

Answer: 41 atm

Explanation:

Given that:

Original Volume of gas V1 = 2.9L

Temperature T1 = 32.7°C

Convert Celsius to Kelvin

(32.7°C + 273 = 305.7K)

Pressure P1 = 645.3 torr

New Volume V2 = 0.23 L

New temperature T2 = 894.7°C

Convert Celsius to Kelvin

(894.7°C + 273 = 1167.7K)

New pressure = ?

Then, apply the combined gas equation

(P1V1)/T1 = (P2V2)/T2

(645.3 torr x 2.9L)/305.7K = (P2 x 0.23L)/1167.7K

1871.37 / 305.7 = 0.23P2 / 1167.7

To get P2, Cross multiply

1871.37 x 1167.7 = 305.7 x 0.23P2

2185198.749 = 70.311P2

Divide both sides by 70.311

2185198.749/70.311 = 70.311P2/70.311

31079.045 torr = P2

Now, convert pressure in torr to atmosphere

Since 760 torr = 1 atm

31079.045 torr = Z

cross multiply

760 torr x Z = 31079.045 torr x 1 atm

Z = 31079.045 torr / 760 torr

Z = 40.89 atm (Round to the nearest whole number as 41 atm)

Thus, new pressure of gas is 41 atm

3 0

3 years ago

Calcium carbide, CaC2, reacts with water to form calcium hydroxide and the flammable gas ethyne (acetylene) in the reaction: Wha

AysviL [449]

Answer:

1 mole of CaC₂ will produce 26g of C₂H₂ or 64.1g of CaC₂ will produce 26g of C₂H₂

Explanation:

Hello,

To solve this question, we'll require a balanced chemical equation of reaction between calcium carbide and water.

Equation of reaction

CaC₂ + 2H₂O → Ca(OH)₂ + C₂H₂

Molar mass of calcium carbide (CaC₂) = 64.1g/mol

Molar mass of water (H₂O) = 18g/mol

Molar mass of calcium hydroxide (Ca(OH)₂) = 74g/mol

Molar mass of ethyne (C₂H₂) = 26g/mol

From the equation of reaction, 1 mole of CaC₂ will produce 1 mole of C₂H₂

1 mole of CaC₂ = mass / molar mass

Mass = 1 × 64.1

Mass = 64.1g

1 mole of C₂H₂ = mass / molar mass

Mass = 1 × 26

Mass = 26g

Therefore, 1 mole of CaC₂ will produce 26g of C₂H₂

Note: this is a hypothetical calculation since we were not given the initial mass of CaC₂ that starts the reaction

7 0

3 years ago

In the following reaction, how many grams of nitroglycerin C3H5(NO3)3 will decompose to give 25 grams of CO2?

gogolik [260]

4C₃H₅(NO₃)₃ $_{(l)}$ ------> 12CO₂ $_{(g)}$ + 6N₂ $_{(g)}$ + 10H₂O $_{(g)}$ + O₂ $_{(g)}$

mol of CO₂ = $\frac{mass}{molar mass}$

= $\frac{25g}{44.01 g/mol}$

mol ratio of CO₂ : C₃H₅(NO₃)₃

12 : 4

∴ if mole of CO₂ = 0.568 mol

then " " C₃H₅(NO₃)₃ = $\frac{0.568 mol}{12} * 4$

= 0.189 mol

∴ mass of nitroglycerin = mole * Mr

= 0.189 mol * 227.0995 g / mol

= 43.00 g

8 0

3 years ago