What is the mass number of an atom with 17 protons 17 electrons and 18 neutrons?
For example, the atomic mass of chlorine (Cl) is 35.45 amu because chlorine is composed of several isotopes, some (the majority) with an atomic mass of 35 amu (17 protons and 18 neutrons) and some with an atomic mass of 37 amu (17 protons and 20 neutrons).
Does chlorine gain or lose electrons?
Chlorine gains an electron, leaving it with 17 protons and 18 electrons. Since it has 1 more electron than protons, chlorine has a charge of −1, making it a negative ion. When ions form, atoms gain or lose electrons until their outer energy level is full.
Is chlorine an electron donor?
The -I effect of chlorine withdraws electrons from the benzene ring. Conversely Cl donates its lone pair of electrons to the aromatic ring and hence increase the electron density at ortho and para positions. Thus, the lone pair of electrons on the chlorine atom stabilize the intermediate carbocation due to resonance.
Is BR electron withdrawing?
Nitro groups are electron-withdrawing groups, so bromine adds to the meta position. The main point to remember here is that electron-donating groups direct substitution to the ortho and para positions, while pi electron-withdrawing groups direct substitution to the meta position.
Is BR Ortho para or meta?
| Electronic Effect | Examples | Direction |
|---|---|---|
| donation – inductive effect | -Alkyl | ortho, para with some meta |
| donation – conjugation, withdrawal – inductive effect | -F, -Cl, -Br, -I | ortho and (mostly) para |
| withdrawal – inductive effect | -CF3 | meta |
| withdrawal – conjugation | -NO2, -CN | meta |
Is chlorine an activating group?
Not all groups capable of pi donation are activating groups. For example, halogens (F, Cl, Br, I) tend to be deactivating. The rates of electrophilic aromatic substitution reactions on fluorobenzene, chlorobenzene, bromobenzene, and iodobenzene are all slower than they are for benzene itself.
Is OCH3 activating or deactivating?
Any group with decreases the rate (relative to H) is called adeactivating group. Common activating groups (not a complete list): Alkyl, NH2, NR2, OH, OCH3, SR. Common deactivating groups (not a complete list): NO2, CF3, CN, halogens, COOH, SO3H.
Which is more activating OH or OCH3?
OH (hydroxy) has a better +R effect than OCH3 because The -CH3 group in -OCH3 causes steric repulsions with lone pairs, increasing bond angles. Due to which it make -O- atom of -OCH3 more electro-negative and thus affecting donor tendency.
Is NO2 EWG or EDG?
NO2 is an amazing electron withdrawing group, along with carbonyls. Electron withdrawing groups make it more difficult to introduce new groups onto the ring. They are also meta directing and deactivate a benzene ring. Electron donating groups generally have a lone pair on the atom directly bonded to the aromatic ring.
Is och3 EWG or EDG?
Yes, OCH3 which belongs to the is the electron-withdrawing group (methoxy group). Here, the oxygen (in OCH3) is more electronegative than carbon due to which it will show -I effect which is electron-withdrawing.
Is benzene EDG or EWG?
Styrene, C6H5-CH=CH2, consists of 2 parts: the benzene ring & the alkene substituent. Together, they will be EDG but they will be weakly activating. For Michael addition reaction , the donor will have 2 EWG groups while the acceptor will have one EWG group.
Is CN EWG or EDG?
Electron withdrawing groups have an atom with a slight positive or full positive charge directly attached to a benzene ring. Examples of electron withdrawing groups: -CF3, -COOH, -CN. This is due to the electron withdrawing group pulling away electrons from the carbon, creating an even stronger positive charge.