Answer:
-56.1kJ/mol
Explanation:
The reaction between HCl and NaOH is:
NaOH + HCl → NaCl + H₂O + ΔH
<em>Where ΔH is heat change in the reaction.</em>
<em />
As the temperature of the solution increases, the heat is released and ΔH < 0
The heat released in the reaction is obtained using coffe-cup calorimeter equation:
Q = C×m×ΔT
<em>Where Q is heat</em>
<em>C is specific heat of the solution (4.184J/g°C)</em>
<em>m is mass of solution: Assuming density = 1g/mL, 100mL of solution = 100g</em>
<em>And ΔT is change in temperature (13.4°C)</em>
<em />
Replacing:
Q = C×m×ΔT
Q = -4.184J/g°C×100g×13.4
Q = -5606.6J
Now, in the reaction you have:
<em>Moles HCl:</em>
0.050L * (2.2mol/L) = 0.11 moles
<em>Moles NaOH:</em>
0.050L * (2.0mol/L) = 0.1 moles
That means the moles of reaction are 0.1 moles, and heat change in the chemical reaction is:
5606.6J / 0.1 mol = 56066J =
<h3>-56.1kJ/mol</h3>
<em />
Answer: A
Explanation: Calculate the molar hydrogen ion concentration of each of the following biological solutions given the pH, Urine pH= 4.90
You will have 0.06502087426717999 moles of NaCl with 3.8 grams. 1 gram= 0.0171107563861
Answer:
1.51 X 10^23 ions
Explanation:
The number of ions in 17.1 gm of aluminum sulphate Al2 (SO4)3 =….. [Molar mass of Al2 (SO4)3 = 342 gm]
in one molecule of Al2(SO4)3 there are 5 ions 2 aluminum and 3 sulfate ions
in 2 molecules there are 2X5= 10 ions
in 10 molecules there are 10X5 = 50 ions
molar mass of Al2(SO4)3 = (2 X 26.98) +( 3 X 32.1) + (3 X 4 X 16.0 ) =342.gms = 17.1/342 =0.0500 moles
1 mole =6.02 X 10^23 molecules ( see Avogadros number)
0.0500 moles = 0.0500 X 6.02 X 10^23 molecules =
0.301 X 10^23 molecules = 3.01 X 10^22 molecules
We determined that each molecule of Al2(SO4)3 has 5 ions
so 3.01 X10^22 molecules have 5 X 3.01 X 10^22 ions =
15.05 X 10^22 ions = 1.51 X 10^23 ions
Hey there!
An energy level is the level of energy that the particle has.
Electrons occupy energy levels.
To release electromagnetic radiation, an electron will absorb energy, jump up an energy level, then releases the energy in the form of a photon and goes back down to its original energy level.
Hope this helps!
