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
blondinia [14]
2 years ago
12

Someone please help me with one of them

Chemistry
1 answer:
EastWind [94]2 years ago
3 0

Explanation:

Are there any values given in the question?

You might be interested in
15. To draw the Lewis structure of the polyatomic ion, ClO3you would have to _____ those in thestructures of Cl, O, O, and O.a.
Contact [7]

To draw the Lewis structure of the polyatomic ion, \mathrm{C} l0_{3} you would have to add one electron to those in the structures of Cl, O, O and O.

Answer: Option A

<u>Explanation:</u>

It is a kind of representation of electrons present in valence shell of each element.  For easy understanding of how the outermost electrons will be arranged for bonding purpose, Lewis structure is used.

As we know that carbon has an outermost electron number of 4. So 4 electrons are required as the electrons in the outermost shell of each carbon. But here only three electrons are there, so one electron need to be added in the Lewis structure of \mathrm{C} l0_{3}.

7 0
3 years ago
Who proposed a heliocentric model of the solar system
alekssr [168]
<span>This theory was first proposed by Nicolaus Copernicus. hope it helps</span>
4 0
2 years ago
Read 2 more answers
Question 16 A chemistry graduate student is given of a methylamine solution. Methylamine is a weak base with . What mass of shou
julsineya [31]

Answer:

90 g CH₃NH₃Cl

Explanation:

It appears your question lacks the values required to solve this problem. However, an online search tells me these are the values. Be aware if your values are different your answer will also be different, but the methodology remains the same.

" A chemistry graduate student is given 450 mL of a 1.70 M methylamine solution. Methylamine is a weak base with Kb=4.4x10⁻⁴. What mass of CH₃NH₃Cl should the student dissolve in the methylamine solution to turn it into a buffer with pH = 10.40 ? You may assume that the volume of the solution doesn't change when the is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits. "

We'll use the <u>Henderson-Hasselbach equation</u>:

  • pH = pKa + log\frac{[Methylamine]}{[Salt]}

So first we <u>use Kb to calculate Ka and then pKa</u>:

  • Ka = Kw/Kb ⇒ Ka = 1x10⁻¹⁴/4.4x10⁻⁴ = 2.27x10⁻¹¹
  • pKa = -log(Ka) = 10.64

Now we can <u>calculate the concentration of the salt</u>, CH₃NH₃Cl:

  • pH = pKa + log\frac{[Methylamine]}{[Salt]}
  • 10.40 = 10.64 + log\frac{1.70}{[Salt]}
  • -0.24 = log\frac{1.70}{[Salt]}
  • 10^{-0.24}=\frac{1.70}{[Salt]}
  • [Salt] = 2.95 M

Now we use the final volume to <u>calculate the moles of CH₃NH₃Cl and finally its mass</u>, using its molecular weight:

  • 450 mL ⇒ 450/1000 = 0.450 L
  • 2.95 M * 0.450 L = 1.3275 mol CH₃NH₃Cl
  • 1.3275 mol CH₃NH₃Cl * 67.45 g/mol = 89.54 g CH₃NH₃Cl

Which when rounded to 2 significant digits becomes 90 g CH₃NH₃Cl

7 0
2 years ago
Which of the following nuclei would be the most stable?
ValentinkaMS [17]
Ten protons would be Neon, but the most stable? I'd have to say 12 neutrons in contrast to the 10 protons.  Not too negative in balance.
6 0
3 years ago
2FeO(s) ⇌ 2Fe(s) + O2(g) K eq = 1 x 10^-6 at 1000 K
SCORPION-xisa [38]

Answer:

b

Explanation:

8 0
3 years ago
Other questions:
  • The most prominent topographical feature of the ocean discovered in the 1960's was _____.
    15·2 answers
  • Which of the following is an example of a synthesis reaction?
    14·1 answer
  • Fungi exist primarily in the form of long filaments called _____.
    9·2 answers
  • Which of the following is the best definition of nodes?
    5·2 answers
  • Please help! Will give brainliest!!!!!!
    11·1 answer
  • Please help me thank you! Stay safe
    14·2 answers
  • How many grams of sodium carbonate contain 1.773 × 1017 carbon atoms
    12·1 answer
  • The black-footed ferret is a highly specialized predator that depends on prairie dogs for survival. Prairie dogs make up more th
    12·1 answer
  • PLEASE HELP it’s due in 30 minutes
    13·1 answer
  • For each of the following atomic numbers, use the periodic
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!