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
Dima020 [189]
3 years ago
13

A compound is found to be 30.45% n and 69.55 % o by mass. if 1.63 g of this compound occupy 389 ml at 0.00°c and 775 mm hg, what

is the molecular formula of the compound?
Chemistry
1 answer:
Charra [1.4K]3 years ago
3 0
1) mass composition

N: 30.45%
O: 69.55%
   -----------
   100.00%

2) molar composition

Divide each element by its atomic mass

N: 30.45 / 14.00 = 2.175 mol

O: 69.55 / 16.00 = 4.346875

4) Find the smallest molar proportion

Divide both by the smaller number

N: 2.175 / 2.175 = 1

O: 4.346875 / 2.175 = 1.999 = 2

5) Empirical formula: NO2

6) mass of the empirical formula

14.00 + 2 * 16.00 = 46.00 g

7) Find the number of moles of the gas using the equation pV = nRT

=> n = pV / RT = (775/760) atm * 0.389 l / (0.0821 atm*l /K*mol * 273.15K)

=> n = 0.01769 moles

8) Find molar mass

molar mass = mass in grams / number of moles = 1.63 g / 0.01769 mol = 92.14 g / mol

9) Find how many times the mass of the empirical formula is contained in the molar mass

92.14 / 46.00 = 2.00

10) Multiply the subscripts of the empirical formula by the number found in the previous step

=> N2O4

Answer: N2O4
You might be interested in
7. Diethyl ether burns in air according to the following equation. C4H10O(l) + 6O2 (g) → 4CO2 (g) + 5H2O(l) If 7.15 L of CO2 is
iren [92.7K]

From the stoichiometry of the combustion reaction, we can see that 7.4 L of oxygen is consumed.

<h3>What is combustion?</h3>

Combustion is a reaction in which a substance is burnt in oxygen. The equation of the reaction is; C4H10O(l) + 6O2 (g) → 4CO2 (g) + 5H2O(l)

We can obtain the number of moles of CO2 from;

PV = nRT

n = 1.02 atm * 7.15 L/0.082 atm LK-1mol-1 * (125 + 273) K

n = 7.29 /32.6

n = 0.22 moles

If 6 moles of oxygen produces 4 moles of CO2

x moles of oxygen produces 0.22 moles of CO2

x = 0.33  moles

1 mole of oxygen occupies 22.4 L

0.33 moles of oxygen occupies 0.33 moles *  22.4 L/ 1 mole

= 7.4 L of oxygen

Learn more about stoichiometry: brainly.com/question/13110055

#SPJ1

6 0
2 years ago
The temperature of a gas is 30 degrees Celsius and its pressure is 760 torr. If the temperature originally
erastova [34]
T₁ = 40°C + 273.15 = 313.15 Kelvin T₂ = 30°C + 273.15 = 303.15 Kelvin

Solving Gay-Lussac's Law for P₁ we get:
P₁ = P₂ • T₁ ÷ T₂ P₁ = 760 torr • 313.15 K ÷ 303.15 K P₁ = 785.07 torr

Using the calculator, we click on the P1 button.
We then enter the 3 numbers 760 313.15 and 303.15 into the correct boxes then click "CALCULATE" and get our answer of 785.07 torr.
6 0
3 years ago
By how much will the ph change if 0.025 mol of hcl is added to 1.00 l of the buffer that contains 0.15 m hc2h3o2 and 0.25 m c2h3
Setler [38]
According to the reaction equation:

              CH3COO-  + H+   → CH3COOH 

initial         0.25                             0.15

change     - 0.025                          + 0.025

Equ         (0.25-0.025)                 (0.15 + 0.025)

first, we have to get moles acetate and moles acetic acid:

moles of acetate = 0.25 - 0.025 = 0.225 moles

∴ [CH3COO-] = 0.225 mol / 1 L = 0.225 M

moles of acetic acid = 0.15 + 0.025 = 0.175 moles

∴ [ CH3COOH] = 0.175 mol / 1L = 0.175 M 

Pka = -㏒ Ka 

       = -㏒ 1.8 x 10^-5
       
       = 4.74

from H-H equation we can get the PH value:

PH = Pka + ㏒ [acetate / acetic acid]

PH = 4.74 + ㏒[0.225/0.175]

∴ PH = 4.8
3 0
3 years ago
6
kumpel [21]

Answer:

Explanationrr

8 0
3 years ago
Type of introduction ​
AlladinOne [14]

Answer:

Five Types of Introductions.

“Inquisitive” Explain why your subject is important, curious, or interesting.

“Paradoxical” Explain what aspects of your subject seem improbable. ...

“Corrective” Explain how your subject has been misunderstood or misrepresented by others. ...

8 0
3 years ago
Other questions:
  • A plot of velocity versus substrate concentration for a simple enzyme-catalyzed reaction produces a _____. This indicates that a
    11·1 answer
  • \The specific heat of aluminum is 0.21 cal g°C . How much heat is released when a 10 gram piece of aluminum foil is taken out of
    11·1 answer
  • Identify whether the atom or ion in each equation shows oxidation or reduction
    6·1 answer
  • Which of the following is true for the actual yield of a reaction?
    11·2 answers
  • Zinc reacts with excess hydrochloric acid to produce zinc chloride and hydrogen gas. What happens to the reaction rate if you in
    11·2 answers
  • All radioactive nuclides undergo what
    15·1 answer
  • PLEASE ANSWER
    6·1 answer
  • NEED ASAP!! WILL GIVE BRAINLIEST!! Only have 10 minutes left please help.
    6·1 answer
  • It has been found by mass spectrometric analysis that in nature, the relative abundances of the various isotopic atoms of silico
    8·1 answer
  • What is Newton's second law of motion ​
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!