Answer:
b) pH = 9.25
Explanation:
- NH4+(aq) + H2O(l) ↔ NH3(aq) + H3O+(aq)
- NH3 + H2O ↔ NH4+ + OH-
- 2 H2O ↔ H3O+ + OH-
⇒ Kb = [ NH4+ ] * [ OH- ] / [ NH3 ] = 1.86 E-5......from literature
mass balance NH4+:
⇒ M NH4+ = [ NH4+ ] - [ OH- ]
∴ [ NH3 ] ≅ M NH4+ = 0.26 M
⇒ Kb = (( 0.26 + [ OH- ] )) * [ OH- ] / 0.26 = 1.86 E-5
⇒ 0.26 [ OH-] + [ OH- ]² = 4.836 E-6
⇒ [ OH- ]² + 0.26 [ OH- ] - 4.836 E-6 = 0
⇒ [ OH- ] = 1.859 E-5 M
⇒ pOH = - Log ( 1.859 E-5 )
⇒ pOH = 4.7305
⇒ pH = 14 - pOH = 9.269
Becoing itsodim fromate t will have pb of 67
Explanation:
the tip of a growing plant contains special rapidly diving cells called apical meristem ,these cells are responsible for increase in the length of the plant . if we cut out these cells ,length growth of the plant will be stunned as these cells are not present anyplace else.
Density is a property of a material which describes the mass of a material per unit volume. Density is said to be slightly dependent on temperature. We look at the density of water at different temperatures:
<span>
100 </span>°C: 958.4 kg/m^360 °C: 983.2 kg/m^320 <span>°C</span>: 998.2 kg/m^3
Therefore, warm water has a lower density than water in colder temperature.
The atoms and molecules in gases<span> are much more spread out than in solids or</span>liquids<span>. They vibrate and move freely at high speeds. A </span>gas<span> will fill any container, but if the container is not sealed, the </span>gas<span> will escape. </span>Gas<span> can be compressed much more easily than a </span>liquid<span> or solid</span>
