1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Feliz [49]
3 years ago
6

A balloon filled with helium occupies 21.0ft³ at 55.0°F. Find the temperature of the helium if the volume of the balloon decreas

es to 11.0ft³. (Assume that the pressure is held constant.)​
Chemistry
1 answer:
harkovskaia [24]3 years ago
6 0

Answer:

Assuming pressure is held constant,the question reduces to a ratio and proportion type of question where;

At constant pressure,

21.0ft³-55.0°F

11.0fy³=11.0ft³/21.0ft³×55°F

The temperature is 28.809°F≈29°F

You might be interested in
Q15. Natural gas burns in air to form carbon dioxide and water to releasing heat. CHA(g) O2 (g) CO2 g) H20 (g) AH 802.3 kJ What
mestny [16]

Answer:

a) 0.115 g

Explanation:

The balanced reaction is:

CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g)

To heat 55g of water, the energy in form of heat necessary can be calculated by:

Q = mcΔT

where Q is the heat, m is the mass, c is the specific heat (for water, c = 4.18 J/gºC), and ΔT is the variation of the temperature, which is 25ºC, so:

Q = 55x4.18x25

Q = 5747.5 J = 5.7475 kJ

So, for the reaction, 1 mol of CH₄ releases 802.3 kJ, so to release 5.7475 kJ will be necessary:

1 mol ---------------- 802.3 kJ

x ---------------- 5.7475 kJ

By a simple direct three rule:

802.3x = 5.7475

x = 7.164x10⁻³mol

The molar mass of CH₄ is : 12 (of C) + 4x1 (of H) = 16 g/mol

The mass is equal to the number of moles multiplied by molar mass, the:

m = 7.164x10⁻³x16

m = 0.115 g

6 0
3 years ago
Calculate kb the base dissociation constant for [c2h3o2-], acetate anion, for each of your trials from the concentrations of spe
Pani-rosa [81]
Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
Ka (mol/L ) = <span>0.00002340</span>

5 0
3 years ago
The hydrogen chloride (HCl) molecule has an internuclear separation of 127 pm (picometers). Assume the atomic isotopes that make
natta225 [31]

Answer:

the energy of the third excited rotational state \mathbf{E_3 = 16.041 \ meV}

Explanation:

Given that :

hydrogen chloride (HCl) molecule has an intermolecular separation of 127 pm

Assume the atomic isotopes that make up the molecule are hydrogen-1 (protium) and chlorine-35.

Thus; the reduced mass μ = \dfrac{m_1 \times m_2}{m_1 + m_2}

μ = \dfrac{1 \times 35}{1 + 35}

μ = \dfrac{35}{36}

∵ 1 μ = 1.66 × 10⁻²⁷ kg

μ  = \\ \\ \dfrac{35}{36} \times 1.66 \times 10^{-27} \ \  kg

μ  = 1.6139 × 10⁻²⁷ kg

r_o = 127 \ pm = 127*10^{-12} \ m

The rotational level Energy can be expressed by the equation:

E_J = \dfrac{h^2}{8 \pi^2 I } \times J ( J +1)

where ;

J = 3 ( i.e third excited state)  &

I = \mu r^2_o

E_J= \dfrac{h^2}{8  \pi  \mu r^ 2 \mur_o } \times J ( J +1)

E_3 = \dfrac{(6.63 \times 10^{-34})^2}{8  \times  \pi ^2  \times 1.6139 \times 10^{-27} \times( 127 \times 10^{-12}) ^ 2  } \times 3 ( 3 +1)

E_3= 2.5665 \times 10^{-21} \ J

We know that :

1 J = \dfrac{1}{1.6 \times 10^{-19}}eV

E_3= \dfrac{2.5665 \times 10^{-21} }{1.6 \times 10^{-19}}eV

E_3 = 16.041  \times 10 ^{-3} \ eV

\mathbf{E_3 = 16.041 \ meV}

8 0
3 years ago
Question 7 of 15
Crazy boy [7]

Answer: 0.4 moles

Explanation:

Given that:

Volume of gas V = 11L

(since 1 liter = 1dm3

11L = 11dm3)

Temperature T = 25°C

Convert Celsius to Kelvin

(25°C + 273 = 298K)

Pressure P = 0.868 atm

Number of moles N = ?

Note that Molar gas constant R is a constant with a value of 0.00821 atm dm3 K-1 mol-1

Then, apply ideal gas equation

pV = nRT

0.868atm x 11dm3 = n x (0.00821 atm dm3 K-1 mol-1 x 298K)

9.548 atm dm3 = n x 24.47atm dm3mol-1

n = (9.548 atm dm3 / 24.47atm dm3 mol-1)

n = 0.4 moles

Thus, there are 0.4 moles of the gas.

3 0
3 years ago
Please help brainiest is award.
sineoko [7]

Answer:

7688

Explanation:

3 0
3 years ago
Other questions:
  • Which of the following was a cause of the French and Indian War?
    10·2 answers
  • Which of these is an example of a physical change? Question 9 options: paper burning wood decaying iron melting steel rusting
    15·1 answer
  • Anions and cations are
    13·2 answers
  • At 500°C the equilibrium constant, Kp, is 4.00 × 10–4 for the equilibrium: 2HCN(g) H2(g) + C2N2(g) What is Kp for the following
    7·1 answer
  • What characterizes a radioactive atom?
    11·1 answer
  • Which organ gives our body the sense to touch, protects it, and helps keep it at the right temperature?
    8·2 answers
  • Waves form when energy is transferred to ocean
    7·1 answer
  • What is the molarity of 2 moles of a compound dissolved in 4 L of water?
    15·1 answer
  • Which of these will water NOT dissolve?
    14·1 answer
  • Help me┐(´ー`)┌thank you in advance ​
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!