The electrical charge of the oxygen ion is -2.
Answer:
pH=8.32
Explanation:
The relevant equilibrium for this problem is
F⁻ + H₂O ↔ HF + OH⁻
With a constant Kb of
Kb=
Kb=
To calculate the value of Kb we use the formula Kw=Ka*Kb, where Kw is the ionization constant of water, 1 * 10⁻¹⁴.
1 * 10⁻¹⁴ = 7.2*10⁻⁴ * Kb
Kb = 1.4 * 10⁻¹¹
So now we have
1.4 * 10⁻¹¹=
We make the assumption that x<<<0.30 M, so we can rewrite the equation of Kb as:
1.4 * 10⁻¹¹=
So [OH⁻]=2.05*10⁻⁶
(2) entropy (4) activation energy
Answer:
3.86 x 10^24 carbon atoms in a 77 gram diamond
Explanation:
A key tool for chemistry and physics is the concept of the mole. The definition of a mole is actually quite simple. One mole is 6.02 x 10^23 of something. Anything. One can say " I have 1 mole of paperclips(PPC) in my closet.". That simply says that there are 6.02 x 10^23 paperclips(PPC) in your closet. It does suggest, however, that you may be demented. One mole of PPC, placed end-to-end, would stretch a LONG way.
Average PPC Length = 4.45 cm
! mole of PPC would stretch (6.02 x 10^23)*(4.45 cm) = 2.68 x 10^24 cm
That is 2.68 x 10^19 km
The distance to the moon is 3.84x10^5 km. So 1 mole of PPC will stretch to the moon and back 6.97 x 10^13 times.
This mental diversion does not answer the question, but it does explain what comes next for calculating the number of carbon atoms in 77 mg of diamond. The brilliant connection that allows this calculation is how 1 mole (Avogadro's Number) ties in with the atomic masses of the elements. The atomic mass of an element, as shown on a periodic table, is also the mass of that element that contain Avogadro's Number of atoms. The atomic mass, written in AMU (atomic mass units) can ALSO be written as the molar mass, in units of grams/mole. That is, the number of grams of that element that would amount to 6.02 x 10^23 (1 mole) of tat element's atoms.
Carbon, with an atomic mass of 12, can be said to have a Molar Mass of 12 grams/mole.
Use the units to guide the calculation needed to find the number of carbon atoms (in this case divide the grams carbon by the molar mass):
(77 grams Carbon)/(12 grams/mole Carbon)
The grams unit cancels and the moles unit moves to the top, leaving a number that is simply moles of carbon.
(77 grams Carbon)/(12 grams/mole Carbon) = 6.42 moles carbon
By definition, 1 mole equals 6.02 x 10^23 carbon atoms.
(6.42 moles carbon)*((6.02 x 10^23 carbon atoms)/mole)
Moles cancel, leaving carbon atoms
= 3.86 x 10^24 carbon atoms in a 77 gram diamond
Answer:
10%
Explanation:
Out of the original layer, only ten percent is transferred to the next
First convert grams to molesusing molar mass of butane that is 58.1 g
3.50g C4H10 x (1 molC4H10)/(58.1g C4H10) = 0.06024 mol C4H10
Now convert moles to molecules by using Avogadro’s number
0.06024 mol C4H10 x (6.022x10^23 molecules C4H10)/(1 molC4H10) = 3.627x10^22 molecules C4H10
And there are 4 carbon atoms in 1 molecule of butane, so usethe following ratio:
3.627 x 10^22 molecules C4H10 x (4 atoms C)/(1 moleculeC4H10)
= 1.45 x 10^23 atoms of carbon are present
of carbon is present in 3.50 g of butane.
Further Explanation:
Mole is a measure of the amount of substance. It is defined as the mass of a substance that has the same number of fundamental units as there are atoms in 12 g of carbon-12. Such fundamental units can be atoms, molecules or formula units.
Avogadro’s number is the number of units that are present in one mole of the substance. Its value is equal to per mole of substance. These units can be electrons, atoms, molecules or ions.
The formula to calculate the moles of butane is as follows:
......(1)
The given mass of butane is 3.50 g.
The molar mass of butane is 58.12 g/mol.
Substitute these values in equation (1).
The molecules of butane are calculated as follows:
......(2)
The moles of butane is 0.060220234 mol.
The value of Avogadro’s number is .
Substitute these values in equation (2).
One molecule of butane has four carbon atoms. So the number of carbon atoms in of butane is calculated as follows:
.......(3)
Substitute for the molecules of butane in equation (3).
Therefore the number of atoms of carbon is .
Learn more:
1. Calculate the moles of chlorine in 8 moles of carbon tetrachloride: brainly.com/question/3064603
2. Calculate the moles of ions in the solution: brainly.com/question/5950133
Answer details:
Grade: Senior School
Subject: Chemistry
Chapter: Mole concept
Keywords: mole, atoms of carbon, molecules of butane, carbon-12, 12 g, Avogadro’s number, butane, moles of butane, electrons, molecules, atoms.
(2) Pb-206 (4) Co-60
I-131 (Iodine-131) is the radioisotope used for diagnosing thyroid disorders. It is selectively taken up by the thyroid gland and its emissions allow for imaging of the gland.
The radioisotope used for diagnosing thyroid disorders is I-131 (Iodine-131). This radioisotope is used in medical procedures due to its unique characteristics. When consumed, it is selectively taken up by the thyroid gland. I-131 emits beta particles and gamma radiation which allows for imaging of the thyroid gland. This in turn helps health professionals diagnose if the thyroid is functioning normally or if disorders such as hyperthyroidism or tumors are present.
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