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
masya89 [10]
3 years ago
8

PLEASE help — I’m failing!

Chemistry
1 answer:
ANEK [815]3 years ago
4 0

Answer:

a.

[H _{3}O {}^{ + }   ] = 4.23 \times  {10}^{ - 3} M

b.

[OH {}^{ - } ] =  \frac{kw}{[H {}^{ + } ]}  \\ [OH {}^{ - } ] =  \frac{1 \times  {10}^{ - 14} }{4.23 \times  {10}^{ - 3} }  \\ [OH {}^{ - } ] = 2.36 \times  {10}^{ - 12} M

c.

pH =  -  log[H {}^{ + } ] \\ pH =  -  log(4.23 \times  {10}^{ - 3} )  \\ pH = 2.37

d.

pOH =  -  log[OH {}^{ - } ] \\  =  -  log(2.36 \times  {10}^{ - 12} )  \\  = 11.63

You might be interested in
During which of the following phases of the moon do we see the left half of the moon as lit?
xxMikexx [17]
During the 3rd quarter
7 0
3 years ago
How many grams of Kr are in a 9.59 L cylinder at 46.0 'C and 4.62 atm?<br> mass:
Sladkaya [172]

Answer:

Mass = 141.6 g

Explanation:

Given data:

Mass of Kr in gram =  ?

Volume in L = 9.59 L

Temperature = 46.0°C

Pressure = 4.62 atm

Solution:

The given problem will be solve by using general gas equation,

PV = nRT

P= Pressure

V = volume

n = number of moles

R = general gas constant = 0.0821 atm.L/ mol.K  

T = temperature in kelvin

Now we will convert the temperature.

46.0+273 = 319 K

4.62 atm × 9.59 L = n× 0.0821 atm.L/ mol.K  ×319 K

44.3 atm.L = n×26.19 atm.L/ mol

n = 44.3 atm.L / 26.19 atm.L/ mol

n = 1.69 mol

Mass in gram:

Mass = number of moles × molar mass

Mass = 1.69 mol × 83.79 g/mol

Mass = 141.6 g

8 0
3 years ago
JWL 3.R 1.096776 x 107 m) L) 384.6 nm C) 683.8 nm D) 1282 nm E) &gt;1500 nm Ans: D According to the Rydberg equation, the line w
sesenic [268]

Answer:

91.2 nm

Explanation:

The Rydberg equation is given by the formula

     1/ λ  = Rh ( 1/ n₁² - 1/ n₂²)

where

λ is the wavelength

Rh is Rydberg constant

and n₁ and n₂ are the energy levels of the transion.

We can see from this equation that the wavelength is inversely proportional to the difference of the squares of the inverse of the quantum numbers n₁ and n₂. It follows then that the smallest wavelength will be given when the the transitions are between the greatest separation between n₁ and n₂ whicg occurs when n1= 1 and n₂= ∞ , that is the greater the separation in energy levels the shorter the wavelength.

Substituting for n₁ and n₂ and solving for λ :

  1/λ = 1.0974 x 10⁷ m⁻¹ x ( 1/1² -1/ ∞²)  =  1.0974 x 10⁷ m⁻¹ x ( 1/1² - 0) =

  λ = 1/1.0974 x 10⁷ m = 9.1 x 10⁻8 m = 91.2 nm

4 0
3 years ago
A student is given two clear solutions. One solution contained lead ions, Pb2+ and the other solution contains chloride ions, Cl
larisa86 [58]
<span>A chemical change has occurred creating a precipitate. 
Just had that question on a quiz. XP

Hope I helped :)</span>
4 0
4 years ago
Read 2 more answers
Based on the representation, which of the following statements about the element is true ?
Greeley [361]

We generally represent an element by its symbol. provided with the atomic number and mass number or atomic mass

Atomic number is the number of protons present in an element. It is constant for an element.

The mass number of element is the sum of number of protons and number of neutrons

The atomic mass is the total mass of all the protons and neutrons present in the element (in its nucleus).

the number of electrons is equal to number of protons in a neutral atom of element.

The mass of electrons is not included in the total atomic mass of element as it is very low.

So here

12 = it is the number of protons = atomic number of element.

The true statements are

The combined mass of protons and neutrons is 24.305



6 0
3 years ago
Read 2 more answers
Other questions:
  • Substances that are more dense have ___________ (lower or higher) specific gravity.
    10·1 answer
  • How many electrons does the isotope oxygen-18 have?<br> 6<br> 8<br> 10<br> 18
    13·1 answer
  • The name of an alkyl group that contains THREE carbon atoms is____
    15·1 answer
  • At a certain fixed temperature, the reaction A(g) + 2 B(g) → AB2(g) is found to be first order in the concentration of A and zer
    7·1 answer
  • A particular reactant decomposes with a half-life of 121 s when its initial concentration is 0.357 M. The same reactant decompos
    15·1 answer
  • . Which of the following is NOT the basic patterns of crystalline structure?
    12·1 answer
  • Explain how a hurricane poses a threat to life and the biosphere. Use complete sentences.
    8·2 answers
  • Give examples of five polymers that are manufactured using technological processes​
    13·1 answer
  • A solution that contains less than the amount of solute that would be dissolved at equilibrium is considered to be
    6·1 answer
  • Choose the compound that is covalent.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!