Answer:
25.53mL of 0.200 M FeCl₃ are needed to produce 0.345g of Fe₂S₃
Explanation:
Based on the reaction of the problem, 1 mole of Fe₂S₃ is produced from 2 moles of FeCl₃.
0.345g of Fe₂S₃ are (Molar mass: 207.9g/mol):
0.345g of Fe₂S₃ ₓ (1 mol / 207.9g) = <em>1.6595x10⁻³ moles Fe₂S₃</em>
Moles of Fe needed to produce these moles of Fe₂S₃ are:
1.6595x10⁻³ moles Fe₂S₃ ₓ ( 2 moles FeCl₃ / 1 mole Fe₂S₃) =
<em>3.3189x10⁻³ moles of FeCl₃</em>
As the percent yield of the reaction is 65.0%, the moles of FeCl₃ you need to add are:
3.3189x10⁻³ moles of FeCl₃ ₓ (100.0% / 65.0%) = <em>5.106x10⁻³ moles of FeCl₃</em>
A solution 0.200M contains 0.200 moles per L. Volume to obtain 5.106x10⁻³ moles is:
<em>5.106x10⁻³ moles of FeCl₃ ₓ ( 1L / 0.200mol) = 0.02553L = </em>
<h3>25.53mL of 0.200 M FeCl₃ are needed to produce 0.345g of Fe₂S₃</h3>
Answer:
4.28x10^24 molecules
Explanation:
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. From the above, we understood that 1mole of H2O also contains 6.02x10^23 molecules.
1mole of H2O = (2x1) + 16 = 2 + 16 = 18g
Now, if 18g of H2O contains 6.02x10^23 molecules,
Then 128g of H2O will contain = (128x 6.02x10^23) /18 = 4.28x10^24 molecules
Answer:but-1-ene
Explanation:This is an E2 elimination reaction .
Kindly refer the attachment for complete reaction and products.
Sodium tert-butoxide is a bulky base and hence cannot approach the substrate 2-chlorobutane from the more substituted end and hence major product formed here would not be following zaitsev rule of elimination reaction.
Sodium tert-butoxide would approach from the less hindered side that is through the primary centre and hence would lead to the formation of 1-butene .The major product formed in this reaction would be 1-butene .
As the mechanism of the reaction is E-2 so it will be a concerted mechanism and as sodium tert-butoxide will start abstracting the primary hydrogen through the less hindered side simultaneously chlorine will start leaving. As the steric repulsion in this case is less hence the transition state is relatively stabilised and leads to the formation of a kinetic product 1-butene.
Kinetic product are formed when reactions are dependent upon rate and not on thermodynamical stability.
2-butene is more thermodynamically6 stable as compared to 1-butene
The major product formed does not follow the zaitsev rule of forming a more substituted alkene as sodium tert-butoxide cannot approach to abstract the secondary proton due to steric hindrance.
Answer:
D. In both, vibrations occur in a parallel direction to the direction of the wave.
Explanation:
It is not true that in both mechanical and electromagnetic waves, vibrations occur in parallel direction to the direction of the wave.
As with all waves, they are disturbances that transfers energy without moving the materials of the medium.
- Electromagnetic waves have only one way of propagation which is a vibration in both parallel and longitudinal direction.
- Mechanical waves can be propagated either in a parallel direction or longitudinal direction and not both.
TMS stands for Tetramethylsilane
Formula : Si(CH₃)₄
It is used as internal standard for chemical shift
In TMS all the four methyl groups are similar thus all the 12 hydrogen are chemically equivalent. They will show proton NMR at same level and which will appear as a singlet.
We have defined this singlet to be as reference set as zero.
Generally the other organic compounds show chemical shift downfield.So have positive chemical shift with respect to TMS shift.
