Answer: 1560632 joules
Explanation:
The change in thermal energy (Q) required to heat ice depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Given that:
Q = ?
Mass of frozen water (ice) = 1kg
C = 4184 J/(kg K)
Φ = (Final temperature - Initial temperature)
= 100°C - 0°C = 100°C
Convert 100°C to Kelvin
(100°C + 273) = 373K
Then, Q = MCΦ
Q = 1kg x 4184 J/(kg K) x 373K
Q = 1560632 joules
Thus, the change in thermal energy is 1560632 joules
Answer:
84.24 g
Explanation:
Given data:
Mass of oxygen = 75 g
Mass of Al required to react = ?
Solution:
Chemical equation:
4Al + 3O₂ → 2Al₂O₃
Number of moles of oxygen:
Number of moles = mass/ molar mass
Number of moles = 75 g/ 32 g/mol
Number of moles = 2.34 mol
Now we will compare the moles of oxygen with Al.
O₂ : Al
3 : 4
2.34 : 4/3×2.34 = 3.12 mol
Mass of Al required:
Mass = number of moles × molar mass
Mass = 3.12 mol × 27 g/mol
Mass = 84.24 g
False. ......................................
Answer:
Explanation:
As an example, the following cell reaction: Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(m) generates a cell voltage of +1.10 V under standard conditions. Calculate and enter delta G degree (with 3 sig figs) for this reaction in kJ/mol.
Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(m)
ΔG = ΔG° + RTInQ
Q = 1
ΔG = ΔG°
ΔG = =nFE°
n=no of electrons transfered.
E° = 1.1v
ΔG° = -2 * 96500 * 1.10
= -212300J
ΔG° =-212.3kJ/mol
<h3>Therefore, the ΔG° = -212.3kJ/mol</h3>
Answer:
The pH of the sample is 3,4.
Explanation:
We calculate the pOH from the formula pOH = -log (OH-). We know that for all aqueous solutions: pH + pOH = 14, and from there we clear pH:
pOH= -log (OH-)=10,60
pH + pOH = 14
pH + 10,60 = 14
pH=14 -10,60
<em>pH=3,4</em>
