Answer:
Energy is absorbed in the form of heat. so the reaction is
ENDO (COMES IN)-THERMIC (HEAT)
Explanation:
What must occur in order for a chemical reaction to be specifically classified as endothermic instead of exothermic?
Atoms are rearranged.
Chemical bonds are formed.
Energy is released in the form of heat.
Energy is absorbed in the form of heat.
Answer:
0.89
Explanation:
You are mixing an acid and a base, so there will be a neutralization reaction.
One of the reactants will be in excess, so we must determine its concentration and then calculate the pH.
<em>Moles of NaOH
</em>
Moles of NaOH = 25 × 0.173
Moles of NaOH = 4.32 mmol
===============
<em>Moles of HCl
</em>
Moles of HCl = 35 × 0.342
Moles of HCl = 12.0 mmol
===============
<em>Amount of excess reactant
</em>
NaOH + HCl ⟶ NaCl +H₂O
<em>n</em>/mmol: 4.32 12.0
The 4.32 mmol of NaOH reacts completely with 4.32 mmol of HCl.
Excess HCl = 12.0 – 4.32
Excess HCl = 7.6 mmol
===============
<em>Concentration of the excess HCl
</em>
Total volume = 25 + 35
Total volume = 60 mL
<em>c </em>= millimoles HCl/millilitres HCl
<em>c</em> = 7.6/60
<em>c</em> = 0.13 mol/L
===============
<em>Calculate the pH
</em>
The HCl dissociates completely to hydronium ions, so
[H₃O⁺] = 0.13 mol·L⁻¹
pH = -log[H₃O⁺]
pH = -log0.13
pH = 0.89
Answer:
C. Water passes into the salt solution, dehydrating bacterial cells and making them harmless.
Explanation:
The salt solution is hypertonic to the bacterial cells and as such, water molecules will move from the bacterial cells into the salt solution, dehydrating the cells and rendering them harmless.
Option A is also true but it is irrelevant to the question asked. Option B and D are wrong.
The correct option is C.
Answer:
exothermic process because the process of association of oxygen and hydrogen is taking place..