Answer:
c. it involves a series of steps, each of which generates a reactive intermediate that brings about the next step
Explanation:
A chain reaction consist of many repeating steps. Chain reaction will never stop until all the reactant has been exhausted. It is more of a cycle of reaction that generate a reactive intermediate that brings about the next step.
Example of a chain reaction is the chlorination of methane.
CH4 + Cl2 ↔ CH3Cl + HCl
CH3Cl + Cl2 ↔ CH2Cl2 + HCl
CH2Cl2 + Cl2 ↔ CHCl3 + HCl
CHCl3 + Cl2 ↔ CCl4 + HCl
Answer:
To speed up a reaction
Explanation:
Heat, as well as catalysts, increase the reaction rate of some chemical reactions since they cause the enzymes or reagents in charge of carrying out the transformation to products to act faster and increase their kinetic energy of reaction.
Answer:
Explanation:
The HF is about five million times as strong as phenol, so it will be by far the major contributor of hydronium ions. We can ignore the contribution from the phenol.
1 .Calculate the hydronium ion concentration
We can use an ICE table to organize the calculations.
HF + H₂O ⇌ H₃O⁺ + F⁻
I/mol·L⁻¹: 2.7 0 0
C/mol·L⁻¹: -x +x +x
E/mol·L⁻¹: 2.7 - x x x
![K_{\text{a}} = \dfrac{\text{[H}_{3}\text{O}^{+}] \text{F}^{-}]} {\text{[HF]}} = 7.2 \times 10^{-4}\\\\\dfrac{x^{2}}{2.7 - x} = 7.2 \times 10^{-4}\\\\\text{Check for negligibility of }x\\\\\dfrac{2.7}{7.2 \times 10^{-4}} = 4000 > 400\\\\\therefore x \ll 2.7\\\dfrac{x^{2}}{2.7} = 7.2 \times 10^{-4}\\\\x^{2} = 2.7 \times 7.2 \times 10^{-4} = 1.94 \times 10^{-3}\\x = 0.0441\\\text{[H$_{3}$O$^{+}$]}= \text{x mol$\cdot$L$^{-1}$} = \text{0.0441 mol$\cdot$L$^{-1}$}](https://tex.z-dn.net/?f=K_%7B%5Ctext%7Ba%7D%7D%20%3D%20%5Cdfrac%7B%5Ctext%7B%5BH%7D_%7B3%7D%5Ctext%7BO%7D%5E%7B%2B%7D%5D%20%5Ctext%7BF%7D%5E%7B-%7D%5D%7D%20%7B%5Ctext%7B%5BHF%5D%7D%7D%20%3D%207.2%20%5Ctimes%2010%5E%7B-4%7D%5C%5C%5C%5C%5Cdfrac%7Bx%5E%7B2%7D%7D%7B2.7%20-%20x%7D%20%3D%207.2%20%5Ctimes%2010%5E%7B-4%7D%5C%5C%5C%5C%5Ctext%7BCheck%20for%20negligibility%20of%20%7Dx%5C%5C%5C%5C%5Cdfrac%7B2.7%7D%7B7.2%20%5Ctimes%2010%5E%7B-4%7D%7D%20%3D%204000%20%3E%20400%5C%5C%5C%5C%5Ctherefore%20x%20%5Cll%202.7%5C%5C%5Cdfrac%7Bx%5E%7B2%7D%7D%7B2.7%7D%20%3D%207.2%20%5Ctimes%2010%5E%7B-4%7D%5C%5C%5C%5Cx%5E%7B2%7D%20%3D%202.7%20%5Ctimes%207.2%20%5Ctimes%2010%5E%7B-4%7D%20%3D%201.94%20%5Ctimes%2010%5E%7B-3%7D%5C%5Cx%20%3D%200.0441%5C%5C%5Ctext%7B%5BH%24_%7B3%7D%24O%24%5E%7B%2B%7D%24%5D%7D%3D%20%5Ctext%7Bx%20mol%24%5Ccdot%24L%24%5E%7B-1%7D%24%7D%20%3D%20%5Ctext%7B0.0441%20mol%24%5Ccdot%24L%24%5E%7B-1%7D%24%7D)
2. Calculate the pH
![\text{pH} = -\log{\rm[H_{3}O^{+}]} = -\log{0.0441} = \large \boxed{\mathbf{1.36}}](https://tex.z-dn.net/?f=%5Ctext%7BpH%7D%20%3D%20-%5Clog%7B%5Crm%5BH_%7B3%7DO%5E%7B%2B%7D%5D%7D%20%3D%20-%5Clog%7B0.0441%7D%20%3D%20%5Clarge%20%5Cboxed%7B%5Cmathbf%7B1.36%7D%7D)
3. Calculate [C₆H₅O⁻]
C₆H₅OH + H₂O ⇌ C₆H₅O⁻ + H₃O⁺
2.7 x 0.0441
C. the square root of 2gh
Explanation:
The square root of 2gh is equivalent to Torricelli's law in the equation.
given expression:
m v² = mgh
to find v, we make it the subject of the expression:
*multiply both sides of the equation by 2:
2 x( m v² )= 2 (mgh)
mv² = 2mgh
*cancel the mass, m appearing on both sides:
v² = 2gh
* find the square root of both side
v = √2gh
Learn more:
Expression brainly.com/question/11207748
#learnwithBrainly
Answer:
0.480 grams
Explanation:
Li₃N(s) + 3D₂O (L) --------------------------> ND₃(g) + 3LiOD (aq)
1 : 3 : 1 : 3
Number of moles (n) = Mass in gram/ Molar Mass
Mass of ND₃ = 160 mg
= 0.16 g
Molar mass of ND₃= [14 + (3 x 2.014 )]
= 14 + 6.042
= 20.042 g/mol
Number of moles of ND₃ = 0.16/20.042
= 0.007983 moles
From the reaction equation, the mole ratio between Heavy water (D₂O ) and ND₃ is 3: 1.
This implies that the number of moles of Heavy water (D₂O ) required
= 3 x 0.007983 moles
= 0.023949 moles
Molar mass of Heavy water (D₂O )= [(2.014 x 2) + 16]
= 20.028 g/mol
Mass in grams of Heavy water (D₂O )= Number of moles x Molar mass
= 0.023949 x 20.028
= 0.4797 grams
≈ 0.480 grams
