Answer:

Explanation:
The number of molecules of KCN can be found by using the formula
<h3>N = n × L</h3>
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
N = 0.00048 × 6.02 × 10²³
We have the final answer as

Hope this helps you
Answer:
58.61 grams
Explanation:
Taking The molecular weight of NaCl = 58.44 grams/mole
<u>Determine how many grams of NaCl to prepare the bath solution </u>
first we will calculate the moles of NaCl that is contained in 6L of 170 mM of NaCI solution
= ( 6 * 170 ) / 1000
= 1020 / 1000 = 1.020 moles
next
determine how many grams of NaCl
= moles of NaCl * molar mass of NaCl
= 1.020 * 58.44
= 58.61 grams
Answer:
The other signal that would indicate the presence of a C= C bond appears close to 3100
.
Explanation:
Bands that appear above 3000
are often unsaturation diagnoses suggest. The band at 3000-
3100
is characteristics for C-H stretching frequencies and normally is overlaps with the ones for alkanes because it is a band of weak intensity.
Answer:
The pH of the solution is 8.
Explanation:
To which options are correct, let us determine the concentration of the hydroxide ion, [OH-] and the pH of the solution. This is illustrated below:
1. The concentration of the hydroxide ion, [OH-] can be obtained as follow:
pOH = –Log [OH-]
pOH = 6
6 = –Log [OH-]
–6 = Log [OH-]
[OH-] = Antilog (–6)
[OH-] = 1x10^–6 mol/L
2. The pH of the solution can be obtained as follow:
pH + pOH = 14
pOH = 6
pH + 6 = 14
pH = 14 – 6
pH = 8.
From the calculations made above,
[OH-] = 1x10^–6 mol/L
pH = 8.
Therefore, the correct answer is:
The pH of the solution is 8
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