Answer:
The "unit" remaining after conversion is atoms.
This is a way to calculate the number of atoms, in an specific mass.
Explanation:
When you have a mass, multiplying the molar mass, "grams" are cancelled, so you finally obtained, number of moles.
Moles . atoms/mol, cancel the word mol so you will find out a number of atoms, present at the mass from, the begining.
For example, how many atoms are in 10 g of NaCl
Molar mass NaCl = Na mass + Cl mass
23 + 35.45 = 58.45 g/m
10 g . 1 / 58.45 mol/g . NA/ 1 mol = 3.42x10²⁰ atoms
NA = Avogadro number
If the final concentration of NOBr = 0.250M
Change in concentration of NOBr = +0.250 M
Change in concentration of NO = -0.250 M
Change is concentration of Br2 = -0.125 M ( since number of moles of Br2 is 0.5 times the number of mole of NOBr)
Final concentration of NO = 0.400-0.250 = 0.150 M
Final concentration of Br2 = 0.245 - 0.125 M = 0.0120 M
Therefore;
Kc = conc (NOBr)^2/ ((conc NO)^2 ×(conc (Br2)
= (0.250²)/(0.150²×0.120)
= 23.148
= 23.1 mol/dm³
Taking into accoun the STP conditions and the ideal gas law, the correct answer is option e. 63 grams of O₂ are present in 44.1 L of O2 at STP.
First of all, the STP conditions refer to the standard temperature and pressure, where the values used are: pressure at 1 atmosphere and temperature at 0°C. These values are reference values for gases.
On the other side, the pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P×V = n×R×T
where:
- P is the gas pressure.
- V is the volume that occupies.
- T is its temperature.
- R is the ideal gas constant. The universal constant of ideal gases R has the same value for all gaseous substances.
- n is the number of moles of the gas.
Then, in this case:
- P= 1 atm
- V= 44.1 L
- n= ?
- R= 0.082
- T= 0°C =273 K
Replacing in the expression for the ideal gas law:
1 atm× 44.1 L= n× 0.082 × 273 K
Solving:
n=1.97 moles
Being the molar mass of O₂, that is, the mass of one mole of the compound, 32 g/mole, the amount of mass that 1.97 moles contains can be calculated as:
= 63.04 g ≈ <u><em>63 g</em></u>
Finally, the correct answer is option e. 63 grams of O₂ are present in 44.1 L of O2 at STP.
Learn more about the ideal gas law:
As temperature increases, the particles will gain kinetic energy causing it to move more rapidly and randomly. However, this causes the gas to expand as the particles will have more energy to roam freely. Hence as temperature increases, Volume increases.
This is based on Charles' Law stating that the volume of a gas is directly proportional to its absolute temperature.
Answer:
The valence shell of noble gases has all 8 valence electrons which means it is full.
Explanation:
