Answer:
a) Addition reaction, is your answer
A ratio of 0.89% w / v or 0.0089 in fraction means that
there is 0.89 weight of NaCl pero volume of solution. Therefore the mass of
NaCl is:
mass NaCl = 0.0089 * 200
<span>mass NaCl = 1.78 grams</span>
A buffer is usually composed of either:
- a weak base combined with its conjugate acid, or
- a weak acid combined with its conjugate base
Now, examining each of the choices:
1- KOH and NH3: since they are both bases, thus this mixture is not a buffer
2- HBr and NaCl: since HBr is a strong acid while NaCl is the salt of another different acid, thus this mixture is not a buffer
3- HCl and HBr: these are both considered to be strong acid, thus this mixture is not a buffer
4- HCHO2 and NaCHO2: as for HCH02, it is considered a weak base while NaCHO2 is considered its conjugate base, thus this mixture is a buffer
