Q1)
the number of moles can be calculated as follows
number of moles = mass present / molar mass
number of moles is the amount of substance.
4.8 g of Ca was added therefore mass present of Ca is 4.8 g
molar mass of Ca is 40 g/mol
molar mass is the mass of 1 mol of Ca
therefore if we substitute these values in the equation
number of moles of Ca = 4.8 g / 40 g/mol = 0.12 mol
0.12 mol of Ca is present
q2)
next we are asked to calculate the number of moles of water present
again we can use the same equation to find the number of moles of water
number of moles = mass present / molar mass
3.6 g of water is present
sum of the products of the molar masses of the individual elements by the number of atoms
H - 1 g/mol and O - 16 g/mol
molar mass of water = (1 g/mol x 2 ) + 16 g/mol = 18 g/mol
molar mass of H₂O is 18 g/mol
therefore number of moles of water = 3.6 g / 18 g/mol = 0.2 mol
0.2 mol of water is present
I just did guessed on the question and got it right. The answer is kinetic energy.
Carbonated drinks have the air under pressure so that carbon bubbles are forced into the drink, keeping it carbonated. So when you open a can, the air under pressure in the can comes out of the can at a high speed, making a "whooshing" sound. The gas law that applies to this concept is the Boyle's Law (PV=k or P1V1=P2V2).
Answer:
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mole
Explanation:
From the balanced
4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2
it is clear that 4 mol FeS₂ react with O₂ to give Fe₂O₃ and 8 mol of SO₂
First, we have to convert mass of SO₂ into No. of moles as following:
SO₂ has molar mass = 64 g/mol
No. of moles of SO₂ = (mass / molar mass) = (32 g / 64 g/mol) = 0.5 mol
we know that
4 mol FeS₂ gives→ 8 mol of SO₂
1 mol FeS₂ gives→ 2 mol of SO₂
??? mol FeS₂ gives→ 0.5 mol of SO₂
No. of moles of FeS₂ = (0.5 mol * 1 mol ) / 2 mol = 0.25 mol
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mol
Answer:
Option (A) saturated and is at equilibrium with the solid KCl
Explanation:
A saturated solution is a solution which can not dissolve more solute in the solution.
From the question given above, we can see that the solution is saturated as it can not further dissolve any more KCl as some KCl is still visible in the flask.
Equilibrium is attained in a chemical reaction when there is no observable change in the reaction system with time. Now, observing the question given we can see that there is no change in flask as some KCl is still visible even after thorough shaking. This simply implies that the solution is in equilibrium with the KCl solid as no further dissolution occurs.
