Answer:
approximately 106 grams
Explanation:
The molecular mass of Aluminum Oxide is approximately 102 grams per mole.
2×Al=
2×27=54
3×O=3×16=48
54+48=102
200
102
=1.96 moles
There are two atoms of Aluminum in one mole and each atom has a mass of approximately 27 grams so
Mass of Al = 1.96×2×27=106 grams
Explanation:
<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
Answer:
Velocity = 120 km/h in north
Speed = 120 km/h
Explanation:
Given data:
Distance = 300 km north
Time taken = 2.5 hr
Speed and velocity = ?
Solution:
Speed = distance / time
Speed = 300 km / 2.5 h
Speed = 120 km/h
Velocity = change in position / change in time
Velocity = 300 km north / 2.5 hr
Velocity = 120 km/h in north
