The molar mass of Na₂SO₄ -
2 x Na - 2 x23 = 46
1 x S - 1 x 32 = 32
4 x O - 4 x 16 = 64
total = 46 + 32 + 64 = 142 g/mol
the molarity of solution - 2.0 M
in 1 L of solution , 2.0 moles
Therefore in 2.5 L - 2 mol/L x 2.5 L = 5 mol
then the mass of Na₂SO₄ required = 142 g/mol x 5 mol = 710 g
Answer:
1) The value of Kc : (C.) remains the same
2) The value of Qc : (A.) is greater than Kc
3) The reaction must : (B.) run in the reverse direction to reestablish equilibrium.
4) The number of moles of Br2 will : (B.) decrease
Explanation:
Value of concentration equilibrium constant Kc depends only on temperature. Since temperature remains constant, therefore, Kc remains constant. Decrease in volume means increase in pressure. Increase in pressure favors the side with less gaseous species. Hence, increase in pressure will favor the reverse reaction towards reactants.
First we need to calculate the number of moles of FeS
:
number of moles = mass (grams) / molecular mass (g/mol)
number of moles of FeS = 198.2/120 = 1.65 moles
From the chemical reaction we deduce that:
if 4 moles of FeS produces 8 moles of SO
then 1.65 moles of FeS produces X moles of SO
X = (1.65×8)/4 = 3.3 moles of SO
Now we can calculate the mass of SO:
mass (grams) = number of moles × molecular mass (grams/mole)
mass of SO = 3.3×64 = 211.2 g
1 mol ------------- 6.02x10²³ atoms
1.14 moles ------ ( atoms )
atoms = 1.14 x ( 6.02x10²³) / 1
atoms = 6.86 x 10²³ / 1
= <span> 6.86 x 10²³ atoms
hope this helps!</span>
