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
Ronch [10]
3 years ago
7

Help me, I’m failing chem

Chemistry
2 answers:
Luba_88 [7]3 years ago
7 0
Trick for the future:
When finding H+ or OH- from pH or pOH, all you need to type into your calculator is:
2nd log - (pH or pOH) to get the answer
For this problem, you would do 2nd log -(3.4) to get an answer of 3.98 x 10 ^ -4 ≈ 4.0 x 10 ^ -4 like the person above said
ladessa [460]3 years ago
5 0

Answer:

b

Explanation:

[H3O+] = 10-pH = 10-3.4 ≅ 3.981 x 10^-4 moles/liter

You might be interested in
For multiple covalent bonds to form in molecules the molecules must contain carbon nitrogen or​
Stella [2.4K]

For multiple covalent bonds to form in molecules, the molecules must contain carbon nitrogen or​ oxygen.

<u>Explanation:</u>

  • Think about carbon dioxide (CO2). If every oxygen atom imparts one electron to the carbon molecule, there will be 6 electrons in carbon particle and 7 electrons in every oxygen atom. This doesn't give the carbon atom as a total octet.
  • Sometimes more than one set of electrons is shared between two atoms. In carbon dioxide, a second electron from every oxygen atom is likewise imparted with the central carbon atom, and the carbon particle imparts one more electron with every oxygen atom.
  • Two sets of electrons shared between two atoms make a double bond between the atoms. A few particles contain triple bonds, covalent bonds in which three sets of electrons are shared by two atoms.

7 0
3 years ago
What causes a spectrum of colors to appear when light moves through a<br><br> prism?
Sonbull [250]

Answer:When light passes through a prism the light bends. As a result, the different colors that make up white light become separated. This happens because each color has a particular wavelength and each wavelength bends at a different angle.

Explanation:

5 0
3 years ago
Read 2 more answers
Iron and aluminim are examples of _________. a. pure substances b. compounds
Ierofanga [76]

Answer:

compounds

Explanation:

8 0
3 years ago
Read 2 more answers
Be sure to use proper significant figures. The molecular weight of NaCl is 58.44 grams/mole. To prepare a 0.50 M solution: You w
Misha Larkins [42]
Your answer would be,
Molarity = moles of solute/volume of solution we needed, 29.22(g)(mol) of NaCI

= 29.22(g)/58.44(g)(mol^-1)(1)/1(L)
= 0.500(mol)(L^-1)



Hope that helps!!!
5 0
3 years ago
Read 2 more answers
C. Use Hess's law and the following equations to calculate ΔH for the reaction 4NH3 (g) + 5O2 (g) 4NO(g) + 6H2 O(g). Show your w
Monica [59]

Considering the Hess's Law, the enthalpy change for the reaction is -906.4 kJ/mol.

<h3>Hess's Law</h3>

Hess's Law indicates that the enthalpy change in a chemical reaction will be the same whether it occurs in a single stage or in several stages. That is, the sum of the ∆H of each stage of the reaction will give us a value equal to the ∆H of the reaction when it occurs in a single stage.

<h3>ΔH in this case</h3>

In this case you want to calculate the enthalpy change of:

4 NH₃ + 5 O₂ → 4 NO + 6 H₂O

which occurs in three stages.

You know the following reactions, with their corresponding enthalpies:

Equation 1: 2 N₂ + 6 H₂ → 4 NH₃   ΔH = –183.6 kJ/mol

Equation 2:  2 N₂ + 2 O₂ → 4 NO     ΔH = 361.1 kJ/mol

Equation 3: 2 H₂ + O₂→ 2 H₂O     ΔH = -483.7 kJ/mol

Because of the way formation reactions are defined, any chemical reaction can be written as a combination of formation reactions, some going forward and some going back.

In this case, first, to obtain the enthalpy of the desired chemical reaction you need 4 moles of NH₃ on reactant side and it is present in first equation on product side. So you need to invert the reaction, and when an equation is inverted, the sign of delta H also changes.

Now, 4 moles of NO must be a product and is present in the second equation, so let's write this as such.

Finally, you need 6 moles of H₂O on the product side, so you need to multiply by 3 the third equation to obtain the amount of water that you need. Since enthalpy is an extensive property, that is, it depends on the amount of matter present, since the equation is multiply by 3, the variation of enthalpy also.

In summary, you know that three equations with their corresponding enthalpies are:

Equation 1: 2 4 NH₃ → N₂ + 6 H₂  ΔH = 183.6 kJ/mol

Equation 2:  2 N₂ + 2 O₂ → 4 NO     ΔH = 361.1 kJ/mol

Equation 3: 6 H₂ + 3 O₂→ 6 H₂O     ΔH = -1,451.1 kJ/mol

Adding or canceling the reactants and products as appropriate, and adding the enthalpies algebraically, you obtain:

4 NH₃ + 5 O₂ → 4 NO + 6 H₂O ΔH= -906.4 kJ/mol

Finally, the enthalpy change for the reaction is -906.4 kJ/mol.

Learn more about Hess's law:

brainly.com/question/5976752

brainly.com/question/13707449

brainly.com/question/13707449

brainly.com/question/6263007

brainly.com/question/14641878

brainly.com/question/2912965

#SPJ1

7 0
2 years ago
Other questions:
  • How could a tsunami affect a coastal ocean ecosystem
    10·1 answer
  • how do scientists apply emission spectra to investigate the chemical composition of stars. 1 page long essay.
    9·2 answers
  • How are physical and chemical changes similar?
    13·2 answers
  • Can someone help me please
    11·1 answer
  • Which of these reactions can be classified as synthesis reactions?
    6·1 answer
  • Phosphorus is most abundant in the
    9·1 answer
  • To calculate the energy released within a calorimeter, the mass, temperature change, and specific heat capacity must be known.
    9·2 answers
  • What is the conjugate base of the following acids?
    7·1 answer
  • During a reaction, H for reactants is -750 kJ/mol and H for products is 920 kJ/mol. Which statement is correct about the reactio
    10·1 answer
  • What is the change in oxidation number of bromine in the following re-dox reaction Cl 2 +2HBr 2HCl+Br 2 A -2;0 B) -1;0 C) 0: -1
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!