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
kogti [31]
3 years ago
6

Diborane (B2H6) is a gas at room temperature that forms explosive mixtures with air. It reacts with oxygen according to the foll

owing equation (which may or may not be balanced): _____ B2H6 (g) + _____ O2 (g) → _____ B2O3 (s) + _____ H2O (l) How many grams of O2 (molar mass 32.00 g/mol) will react with 14.67 grams of diborane (molar mass 27.67 g/mol). Your answer must be expressed to the correct number of significant figures, and with the correct unit.
Chemistry
1 answer:
stiv31 [10]3 years ago
3 0

Answer: 50.91 grams

Explanation:

\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}    

\text{Moles of} B_2H_6=\frac{14.67g}{27.67g/mol}=0.5302moles

The balanced chemical equation is :

B_2H_6(g)+3O_2(g)\rightarrow B_2O_3(s)+3H_2O(l)

According to stoichiometry :

1 mole of B_2H_6 require  = 3 moles of O_2

Thus 0.5302 moles of B_2H_6 will require =\frac{3}{1}\times 0.5302=1.591moles of O_2

Mass of O_2=moles\times {\text {Molar mass}}=1.591moles\times 32.00g/mol=50.91g

Thus 50.91 grams of O_2 reacts with 14.67 g of diborane

You might be interested in
Caffeine (C8H10N4O2) is a weak base with a pKb of 10.4. Calculate the pH of a solution containing a caffeine concentration of 41
RSB [31]

Answer:

pH → 7.47

Explanation:

Caffeine is a sort of amine, which is a weak base. Then, this pH should be higher than 7.

Caffeine + H₂O  ⇄  Caffeine⁺  +  OH⁻      Kb

1 mol of caffeine in water can give hydroxides and protonated caffeine.

We convert the concentration from mg/L to M

415 mg = 0.415 g

0.415 g / 194.19 g/mol = 2.14×10⁻³ mol

[Caffeine] = 2.14×10⁻³  M

Let's calculate pH. As we don't have Kb, we can obtain it from pKb.

- log Kb = pKb → 10^-pKb = Kb

10⁻¹⁰'⁴ = 3.98×10⁻¹¹

We go to equilibrium:

Caffeine + H₂O  ⇄  Caffeine⁺  +  OH⁻      Kb

Initially we have 2.14×10⁻³ moles of caffeine, so, after the equilibrium we may have (2.14×10⁻³ - x)

X will be the amount of protonated caffeine and OH⁻

     Caffeine     +    H₂O  ⇄  Caffeine⁺  +  OH⁻      Kb

   (2.14×10⁻³ - x)                         x                x

We make the expression for Kb:

3.98×10⁻¹¹ = x² / (2.14×10⁻³ - x)

We can missed the -x in denominator, because Kb it's a very small value.

So: 3.98×10⁻¹¹ = x² / 2.14×10⁻³

√(3.98×10⁻¹¹ . 2.14×10⁻³) = x → 2.92×10⁻⁷

That's the [OH⁻].  - log [OH⁻] = pOH

- log 2.92×10⁻⁷ = 6.53 → pOH

14 - pOH = pH → 14 - 6.53 = 7.47

4 0
3 years ago
In which situation is no work considered to be done by a force?
Masja [62]

If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.

If the angle is 45, then there is still some work involved.

The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90. 

7 0
3 years ago
Read 2 more answers
What is a problem that would likely occur if two cultures had different calenderars
aksik [14]
The Sun, Moon, and stars have helped people for thousands of years. When you look into the sky, you will notice that they follow certain patterns. This happens most of the time, but not all of the time. Since most patterns repeat over and over, they have helped us keep track of time. These patterns have also helped us make calendars. Making calendars was a difficult task. Our ancestors had to decide on the length of a year. Also, they had to decide on the length of a day. As you know a day takes 24 hours. That is the time that Earth takes to rotate once on its axis. A year is longer and takes 365 days. This length of time is related to the time that it takes for Earth to go around the Sun. However, this is not exactly true. Earth’s trip takes 365 days – plus a fraction of another day. This is what complicates our calendar. We have been able to solve this problem by adding an extra day in the month of February. Most often, you will see that February has 28 days. Every four years, February has one extra day. During this year we end up with 29 days in this month. When this happens, the year is called a Leap Year. It helps us keep our calendar in order. Deciding on the length of a month has also been a challenge. Some cultures around the world have used a lunar calendar. A lunar calendar is based on the Moon’s cycle. The Moon takes 29 and one-half days to complete one cycle. Then things got a lot harder. Different cultures start their months at a different time of the Moon’s cycle. For example, the Hebrew and Islamic calendars start their months when a crescent moon is seen in the sky. The Chinese start their new months at the new moon phase. These differences have made it harder for cultures to communicate. Trading with one another has also been hard for this reason. As time went by, most countries began to use the same calendar. When this happened in the twentieth century, trade and communication became a lot easier. Some countries decided to drop thirteen days from their calendar. This is because their old way of counting did not match up with the new way. England had problems with the calendar back in the 1500s. The English decided to divide their calendar into months. Each month had four weeks. By doing this, one week ended up being longer than seven days. Also, this resulted in thirteen months to a yea
3 0
3 years ago
Read 2 more answers
An atom of an element has 5 electrons in L-shell.
pishuonlain [190]
I dont know your question but that is true
6 0
3 years ago
What is the average mass of an electron? A. 1 amu B. 1,837 amu C. 1/1,837
diamong [38]

Answer:

C. 1/1,837

Explanation:

3 0
3 years ago
Other questions:
  • Alcohol __________ by making it difficult to anticipate driving situations.
    9·2 answers
  • A sample of iodine is easiest to ship as a powder because it is , making it easy to break into small pieces.
    7·2 answers
  • What is the density of chlorine gas (MM = 71.0glmol) at 1.50 atm and 25.0C
    11·1 answer
  • You chill your reaction in an ice bath when adding nitric acid to the sulfuric acid. why?
    15·1 answer
  • Write the Ground state electron configuration of Ca using the noble-gas shorthand notation
    12·1 answer
  • Can you always tell by looking at a substance if it is pure or not? ​
    10·1 answer
  • What is the ratio of hydrogen molecules to ammonia molecules<br> in the following reaction
    12·1 answer
  • Determine the approximate mass of the isotope of carbon in the image.
    11·1 answer
  • Why is there no answer
    11·2 answers
  • 1. we used __________ to represent an element.
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!