What is the atomic number of the element shown? O A. 26 B. 27.0 C. 40.0 D. 13

A container is filled with hydrogen gas. It has a volume of 4 liters and a pressure of 2 atm. If the pressure of the container i

Dennis_Churaev [7]

Answer:

1.33 L.

Explanation:

We can use the general law of ideal gas: PV = nRT.

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

If n and T are constant, and have different values of P and V:

(P₁V₁) = (P₂V₂)

Knowing that:

V₁ = 4.0 L, P₁ = 2.0 atm,

V₂ = ??? L, P₂ = 6.0 atm.

Applying in the above equation

(P ₁V₁) = (P₂V₂)

∴ V₂ = P ₁V₁/P₂ = (2.0 atm)(4.0 L)/(6.0 atm) = 1.33 L.

4 0

3 years ago

What is the energy of a wave with wavelength of 4.2 x 10-7 m. (Hint: Calculate for frequency first.)

erik [133]

Answer:

Option B. 4.74×10¯¹⁹ J.

Explanation:

The following data were obtained from the question:

Wavelength (λ) = 4.2×10¯⁷ m

Energy (E) =.?

Next, we shall determine the frequency of the wave. This can be obtained as follow:

Wavelength (λ) = 4.2×10¯⁷ m

Velocity (v) = constant = 3×10⁸ m/s

Frequency (f) =.?

v = λf

3×10⁸ = 4.2×10¯⁷ × f

Divide both side by 4.2×10¯⁷

f = 3×10⁸ / 4.2×10¯⁷

f = 7.143×10¹⁴ s¯¹

Therefore, the frequency of the wave is 7.143×10¹⁴ s¯¹.

Finally, we shall determine the energy of the wave using the following formula

E = hf

Where

E is the energy.

h is the Planck's constant

f is the frequency

Thus, the enery of the wave can be obtained as follow:

Frequency (f) = 7.143×10¹⁴ s¯¹.

Planck's constant = 6.63×10¯³⁴ Js

Energy (E) =..?

E = hf

E = 6.63×10¯³⁴ × 7.14×10¹⁴

E = 4.74×10¯¹⁹ J

Therefore, the energy of the wave is 4.74×10¯¹⁹ J.

5 0

3 years ago

Which of the following elements is represented by the above graphic

kolezko [41]

Answer:

Sulfur

Explanation:

Sulfur has 16 valence electrons, as shown in the diagram.

5 0

2 years ago

Calculate the number of moles of ethanol acid in 30 cm³of 1 mol dm-³ solution

muminat

Answer:

May I assume "ethanol acid is just ethanol (it has one slightly acidic H atom). If so, the molar mass is 46.02 g/mole.

Explanation:

We have 30 cm^3 [30 ml] of 1.0 M (1 mole/liter) [1 dm³ = 1 liter].

That is 1 mole/liter. 30 ml would contain (0.030 liter)*(1 mole/1 liter) = 0.03 moles.

7 0

3 years ago

92 grams of ethanol,C2H5OH, is dissolved in 1 liter of solution. Determine the molarity (M)

const2013 [10]

Answer: 1.997 M

Explanation:

molarity = moles of solute/liters of solution or $M = \frac{mol}{L}$

first we have to find our moles of solute (mol), which you can find by dividing the mass of solute by molar mass of solute

mass of solute: 92 g

molar mass of solute: 46.08 g/mol

let's plug it in:

$\frac{92 g}{46.08 g/mol} = 1.997 mol$

next, we plug it into our original equation:

$\frac{1.997mol}{1 L} = 1.997 M$

4 0

3 years ago