MgSO₄ + Pb(NO₃)₂ = PbSO₄(s) + Mg(NO₃)₂
Mg²⁺ + SO₄²⁻ + Pb²⁺ + 2NO₃⁻ = PbSO₄ + Mg²⁺ 2NO₃⁻
Pb²⁺ + SO₄²⁻ = PbSO₄
True a negative change in enthalpy means an exothermic reaction
The balanced equation for the above reaction is as follows;
2Al + 3Br₂ --> 2AlBr₃
stoichiometry of Al to Br₂ is 2:3
there are 5.0 mol of Al and 6.0 mol of Br₂
if Al is the limiting reactant,
if 2 mol of Al reacts with 3 mol of Br₂
then 5.0 mol of Al reacts with - 3/2 x 5 = 7.5 mol of Br₂
but only 6 mol of Br₂ is present therefore Br₂ is the limiting reactant.
if 3 mol of Br₂ reacts with 2 mol of Al
then 6.0 mol of Br₂ reacts with - 2/3 x 6 = 4 mol of Al
the molar ratio of Al to AlBr₃ is 2:2
the number of moles of AlBr₃ formed is 4 mol of AlBr₃
amount of excess Al - 5.0 mol - 4.0 mol = 1 mol
therefore at the end of the reaction,
1 mol of Al and 4 mol of AlBr₃ in the reaction vessel
Answer : The total pressure in the flask is 1.86 atm.
Explanation :
First we have to calculate the pressure of gas.
Using ideal gas equation :
where,
P = Pressure of gas = ?
V = Volume of gas = 765 mL = 0.765 L (1 L = 1000 mL)
n = number of moles
w = mass of gas = 1.25 g
M = molar mass of gas = 44 g/mol
R = Gas constant =
T = Temperature of gas =
Putting values in above equation, we get:
Now we have to calculate the total pressure in the flask.
Given :
conversion used : (1 atm = 760 mmHg)
Now put all the given values in the above expression, we get:
Therefore, the total pressure in the flask is 1.86 atm.
SI unites are based on multiplying or dividing by 10, 100, 1,000, 10,000 (and so on...) depending on the unit you're solving for.