Answer:
0.5059kg
Explanation:
The heat absorbed for the water is determined using the equation:7
Q = C×m×ΔT
<em>Where Q is heat absorbed (4300cal)</em>
<em>C is specific heat (1cal/g°C)</em>
<em>m is the mass in grams</em>
<em>ΔT is change in °C (101.0°C - 92.5°C = 8.5°C)</em>
<em />
Replacing:
4300cal = 1cal/g°C×m×8.5°C
505.9g = m
In kg, the mass of water is:
<h3>0.5059kg</h3>
<em />
Answer:
16.6 g of Al are produced in the reaction of 82.4 g of AlCl₃
Explanation:
Let's see the decomposition reaction:
2AlCl₃ → 2Al + 3Cl₂
2 moles of aluminum chloride decompose to 2 moles of solid Al and 3 moles of chlorine gas.
We determine the moles of salt:
82.4 g . 1mol/ 133.34g = 0.618 moles
Ratio is 2:2. 2 moles of salt, can produce 2 moles of Al
Then, 0.618 moles of salt must produce 0.618 moles of Al.
Let's convert the moles to mass → 0.618 mol . 26.98g /mol = 16.6 g
I believe it's answer #3. Logically, at least.
You can test #1 through trial and error.
You can experiment #2 also through trial and error.
You cannot test #3 through trial and error, because that would be catastrophic.
You can test #4 through a survey and individual study and data collection.
<u>Given:</u>
Mass of Ag = 1.67 g
Mass of Cl = 2.21 g
Heat evolved = 1.96 kJ
<u>To determine:</u>
The enthalpy of formation of AgCl(s)
<u>Explanation:</u>
The reaction is:
2Ag(s) + Cl2(g) → 2AgCl(s)
Calculate the moles of Ag and Cl from the given masses
Atomic mass of Ag = 108 g/mol
# moles of Ag = 1.67/108 = 0.0155 moles
Atomic mass of Cl = 35 g/mol
# moles of Cl = 2.21/35 = 0.0631 moles
Since moles of Ag << moles of Cl, silver is the limiting reagent.
Based on reaction stoichiometry: # moles of AgCl formed = 0.0155 moles
Enthalpy of formation of AgCl = 1.96 kJ/0.0155 moles = 126.5 kJ/mol
Ans: Formation enthalpy = 126.5 kJ/mol