Answer is: because weak acids do not dissociate completely.
The strength of an Arrhenius
acid determines percentage of ionization of acid and the number of H⁺ ions formed. <span>
Strong acids completely ionize in water and give large amount ofhydrogen ions (H</span>⁺), so we use only one arrow, because reaction goes in one direction and there no molecules of acid in solution.
For example hydrochloric acid: HCl(aq) → H⁺(aq) + Cl⁻(aq).
<span>
Weak acid partially ionize in water
and give only a few hydrogen ions (H</span>⁺), in the solution there molecules of acid and ions.
For example cyanide acid: HCN(aq) ⇄ H⁺(aq)
+ CN⁻(aq).
The answer is False. the amplitude shows how high or low something is
Answers:
1) <span>Breaking Solvent-Solvent Attractions is an Endothermic Process.
2) </span><span>Breaking Solute-Solute Attractions is an Endothermic Process.
3) </span><span>Forming Solute-Solvent Attractions is an Exothermic Process.
Explanation:
When a solute is dissolved in solvent it either releases heat or absorbs heat depending upon the the interactions broken and interactions formed. At first, the solvent solvent interactions are broken , this process requires heat which is provided either from external source or is provided by the forming of solute solvent bond forming process which is exothermic.
When the solvent molecules get apart the solute particles enter to form interactions with elimination of heat. So, if the heat required to break solvent solvent interactions is greater than the heat provided by solute solvent interactions formation then the solute will not dissolve at room temperature and vice versa.</span>
Mg + 1/2 O2 → MgO
1 mol = 24 g of Mg
X mol = 12 g of Mg
x = 0.5 moles of Mg
Mg :MgO = 1:1 (coefficient from equations using mole ratio)
So
0.5 moles of MgO
1 mol MgO = (24+16) g = 40 g
0.5 moles of MgO = 0.5 × 40
= 20 g of MgO produced