Molarity is expressed as
the number of moles of solute per volume of the solution. For example, we are
given a solution of 2M NaOH this describes a solution that has 2 moles of NaOH
per 1 L volume of the solution. We calculate as follows:
0.115 M = n mol KBr / .55 L solution
n = 0.06325 mol KBr
mass = 0.06325 mol KBr (119 g / mol) = 7.53 g KBr
Answer:
The number of moles of potassium hydroxide, KOH required to make 4 moles of K₂SO₄ is 8 moles of KOH
Explanation:
2KOH + H₂SO₄ → K₂SO₄ + 2H₂O
From the above reaction, we have 2 moles of KOH combining with 1 mole of H₂SO₄ to produce 1 mole of K₂SO₄ and 2 moles of H₂O.
Therefore the number of moles of potassium hydroxide that will be needed to make 4 moles of K₂SO₄ is;
8KOH + 4H₂SO₄ → 4K₂SO₄ + 8H₂O
8 moles of KOH is required to make 4 moles of K₂SO₄.
<span>Well... first, let's recognize that the chemical formula for chlorodifluoromethane is CHClF2. Count out how many valence electrons there are. C = 4, H = 1, Cl = 7, F (X2) = 14. Total is 26. Let's put C as the central atom, and put the other elements surrounding it. Draw a pair of electrons beach each element and the central atom. Then fill the halogen elements with 3 pairs of electrons each to fill their octets. Count out how many dots you have. There should be 26, making this the correct lewis structure!
Remember, hydrogen doesn't have a full octet, only a maximum of two electrons.</span>
<span>ideal gas law is: PV = nRT
P = pressure (torr) = 889 torr
V = volume (Liters) = 11.8 L
n = moles of gas = 0.444 mol
R = gas constant = 62.4 (L * torr / mol * k)
solve for T (in kelvin)
T = PV/nR
T = (889*11.8)/(.444*62.4)
T = 378.6 K
convert to C (subtract 273)
T = 105.6 deg C</span>
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
