ES6 Flashcards
(20 cards)
Why can HCl(g) produce conc. HCl(aq)?
Made of cov.mlcs so has high solubility [dissolved produces hydrated ions, H+/Cl-]
Halides become stronger reducing agents _______ the group.
Down
Halogens become stronger oxidising agents _______ the group.
Up
What happens when conc. H2SO4 reacts with NaF(s)? What type of reaction?
-> HF(g) + NaHSO4. Not a redox reaction.
What happens when conc. H2SO4 reacts with NaCl(s)? What type of reaction?
-> HCl(g) + NaHSO4. White fumes produced when HCl(g) meets moist air as HCl(aq) formed. Not a redox reaction.
***What happens when conc. H2SO4 reacts with NaBr(s)? What type of reaction?
-> HBr(g) + Br2(g) + SO2(g) +
Reaction is exothermic & redox
***What happens when conc. H2SO4 reacts with NaI(s)? What type of reaction?
-> HI(g) + White fumes (HI) & rotten egg smell (H2S) Redox
How do you make H halides in a lab?
NaCl + H2SO4
NaBr + H3PO4
NaI + H3PO4
(As H3PO4 won’t be reduced & all acids conc.)
Thermal stability _______ the group.
Increases up.
What happens when HF & HI are heated in a lab?
HF is not broken down. HI releases lots of purple I2(g) if red hot needle plunged into HI(g).
What happens when HBr & HCl are heated in a lab?
HCl is not broken down. HBr releases some Br2(g) if heated strongly.
Acidity _______ the group.
Increases down.
\_\_\_\_\_\_\_ = strongly acidic & almost 100% dissociation occurs. \_\_\_\_\_\_\_ = acidic
HCl, HBr & HI. HF.
What do acidic (aq) have?
H+ or H3O+ (oxonium ion)
How to halides react with NH3? What happens if a glass rod dipped in conc. NH3 placed in H halide?
All react to form salts. White cloud ammonium halide (NH4Cl(s))
Intensity of reaction with H2SO4 _______ the group.
Increases down.
What does e. H halide produce when reacted w/ H2SO4? Why do they differ?
HF & HCl = no reaction. HBr = SO2. HI = H2S. Incr. strength of reducing agent down gr.
What is % atom economy?
% of reactant atoms ending up in desired product. Inversely proportional to waste.
What is the calculation for % atom economy?
(desired product Mr / all reactants used Mr) x 100%
How can you make HCl (aq)?
Make HCl(g) from elems or as a co-product from chlorination of organic cmpds
