1 mole of any substance contains 6.022 × 1023 particles.
⚛ 6.022 × 1023 is known as the Avogadro Number or Avogadro Constant and is given the symbol NA
N = n × NA
· N = number of particles in the substance
· n = amount of substance in moles (mol)
· NA = Avogardro Number = 6.022 × 10^23 particles mol-1
For H2O we have:
2 H at 1.0 each = 2.0 amu
1 O at 16.0 each = 16.0 amu
Total for H2O = 18.0 amu, or grams/mole
It takes 18 grams of H2O to obtain 1 mole, or 6.02 x 1023 molecules of water. Think about that before we answer the question. We have 25.0 grams of water, so we have more than one mole of water molecules. To find the exact number, divide the available mass (25.0g) by the molar mass (18.0g/mole). Watch how the units work out. The grams cancel and moles moves to the top, leaving moles of water. [g/(g/mole) = moles].
Here we have 25.0 g/(18.0g/mole) = 1.39 moles water (3 sig figs).
Multiply 1.39 moles times the definition of a mole to arrive at the actual number of water molecules:
1.39 (moles water) * 6.02 x 1023 molecules water/(mole water) = 8.36 x 1023 molecules water.
That's slightly above Avogadro's number, which is what we expected. Keeping the units in the calculations is annoying, I know, but it helps guide the operations and if you wind up with the unit desired, there is a good chance you've done the problem correctly.
N = n × (6.022 × 10^23)
1 grams H2O is equal to 0.055508435061792 mol.
Then 23 g of H2O is 1.2767 mol
To calculate the number of particles, N, in a substance:
N = n × NA
N = 1.2767 × (6.022 × 10^23)
N= 176.26
N=
M/V=D
65.14/35.4≈1.84
The density of the sulfuric acid would be about 1.84g/mL
The mass of oxygen collected from the thermal decomposition of potassium chlorate at a temperature of 297 K and 762 mmHg is 0.16 g
<h3>How to determine the mole of oxygen produced </h3>
We'll begin by obtaining the number of mole of oxygen gas produced from the reaction. This can be obtained by using the ideal gas equation as illustrated below:
- Volume (V) = 0.128 L
- Temperature (T) = 297 K
- Pressure (P) = 762 – 22.4 = 739.6 mmHg
- Gas constant (R) = 62.363 mmHg.L/Kmol
- Number of mole (n) =?
PV = nRT
739.6 × 0.128 = n × 62.363 × 297
Divide both sides by 62.363 × 297
n = (739.6 × 0.128) / (62.363 × 297)
n = 0.0051 mole
Thus, the number of mole of oxygen gas produced is 0.0051 mole
<h3>How to determine the mass of oxygen collected</h3>
Haven obtain the number of mole of oxygen gas produced, we can determine the mass of the oxygen produced as follow:'
- Mole = 0.0051 mole
- Molar mass of oxygen gas = 32 g/mole
- Mass of oxygen =?
Mole = mass / molar mass
0.0051 = mass of oxygen / 32
Cross multiply
Mass of oxygen = 0.0051 × 32
Mass of oxygen = 0.16 g
Thus, we can conclude that the mass of oxygen gas collected is 0.16 g
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Answer:
C4H9OH + 6O2 → 4CO2 + 5H2O
Explanation:
The mole fraction of helium is 0.33.
The mole fraction can be calculated with the aid of dividing the number of moles of 1 factor of an answer by means of the overall number of moles of all the additives of a solution. it's far noted that the sum of the mole fraction of all the components in the solution should be same to one.
Mole fraction is a unit of attention. within the answer, the relative amount of solute and solvents are measured by the mole fraction and it is represented. The mole fraction is the wide variety of moles of a specific thing within the solution divided by way of the entire wide variety of moles.
Mole fraction represents the quantity of molecules of a selected thing in a combination divided by using the total variety of moles within the given mixture. it is a manner of expressing the concentration of a solution. consequently, the sum of mole fraction of all of the additives is always equal to one.
Mole of neon = 1
mole of helium = 2
mole of argon = 3
Total mole = 1 + 2 + 3 = 6
Mole fraction = mole of helium / total mole
= 2 / 6 = 0.33
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