a) The reaction is exothermic since the overall enthalpy change is negative. this means that the system has lost energy to the environment, namely, the apparatus and due to drought.
b) We first calculate the number of moles in 3.55 grams of magnesium.
number of moles= mass/ atomic mass
=3.55/24
=0.1479 moles(to 4sf)
now, if 2 moles of magnesium give -1204kJ
How much energy is given by 0.1479 moles
= (0.1479×-1204kJ)
=-89.0358kJ (don't forget the negative sign)
c) two molesof MgO produces -1204kJ of energy
then -234kJ will be produced by
=(-234kJ×2moles)/1204kJ
=0.3887moles
one mole of MgO weighs 24+16=40
therefore the mass produced is 0.3887moles×40=15.548grams
(d) we first find the number of moles of MgO in 40.3 grams
number of moles=mass/RFM
=40.3g/40= 1.0075moles
if 2 moles of MgO give 1204 kJ then decomposing 1.0075 moles requires
(1.0075 moles×1204kJ)/2=606.515kJ
Answer:
Neutral nucleophile are: H2O, CH3OH, NH3, RNH2, R2NH, R3N, RCOOH, RSH and PR3. The products by nucleophilic substitution are diverse depending on the different nucleophiles, obtaining alcohol, eter, amines, ester and tioeter considering only the nucleophiles with a hydrogen available.
Explanation:
Please see the images attached.
Nucleophilic subtitution with water occurs under Sn1 mechanism. That's it because water as nucleophile is so weak. With the other neutral nucleophiles, the reaction occur under Sn2 mechanism.
RSH + CH3I -----> RSCH3 + HI
Answer: option 4. polar, with the chlorine end having a partial negative charge.
Explanation:
1) A polar bond is a covalent bond in which the electrons are pulled more strongly by one of the atoms and then they are not evely distributed between the two linked atoms.
2) That happens when the two atoms have diferent electronegativities.
3) As the per periodic table trend of the electronegativity, you can predict that the electronetativity of Cl is higher than that of P.
In fact, in a table of electronegativities you can find that the electronegativity of Cl is 3.16 while the electronegativity of P is 2.19.
This is a 3.16 - 2.19 = 0.97 difference.
As explained, that difference means that Cl will pull the electrons more strongly resulting if a partial negative charge on Cl and a partial positive charge on P, i.e. a polar bond.
Answer:
Elements that have atomic numbers from 20 to 83 are heavy elements, therefore the ratio is different. The ratio is 1.5:1, the reason for this difference is because of the repulsive force between protons: the stronger the repulsion force, the more neutrons are needed to stabilize the nuclei.
<span>Hydrogen atoms accompany electrons as they are transferred in biological systems in order to ensure that the metabolism proceeds to completion.
This is considered the main purpose of the electron shuttles.
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