Answer:
Q = 0.50
No
Left
Explanation:
At a generic reversible equation
aA + bB ⇄ cC + dD
The reaction coefficient (Q) is the ratio of the substances concentrations:
![Q = \frac{[C]^c*[D]^d}{[A]^a*[B]^b}](https://tex.z-dn.net/?f=Q%20%3D%20%5Cfrac%7B%5BC%5D%5Ec%2A%5BD%5D%5Ed%7D%7B%5BA%5D%5Ea%2A%5BB%5D%5Eb%7D)
Solids and liquid water are not considered in this calculus.
When the reaction achieves equilibrium (concentrations are constant), the Q value is named as Kc, which is the equilibrium constant of the reaction. If Q > Kc, it indicates that the concentration of the products is higher, so, the reaction must progress to the left and form more reactants; if Q < Kc, than the concentrations of the reactants, are higher, so, the reaction progress to the right.
In this case:
Q = ![\frac{[NO_2]^2}{[N_2O_4]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BNO_2%5D%5E2%7D%7B%5BN_2O_4%5D%7D)
Q = 0.50
So, Q > Kc, the reaction is not at equilibrium and it progresses to the left.
1) Calculate the number of moles of O2 (g) in 300 cm^3 of gas at 298 k and 1 atm
Ideal gas equation: pV = nRT => n = pV / RT
R = 0.0821 atm*liter/K*mol
V = 300 cm^3 = 0.300 liter
T = 298 K
p = 1 atm
=> n = 1 atm * 0.300 liter / [ (0.0821 atm*liter /K*mol) * 298K] = 0.01226 mol
2) The reaction of a metal with O2(g) to form an ionic compound (with O2- ions) is of the type
X (+) + O2 (g) ---> X2O or
2 X(2+) + O2(g) ----> X2O2 = 2XO or
4X(3+) + 3O2(g) ---> 2X2O3
In the first case, 1 mol of metal react with 1 mol of O2(g); in the second case, 2 moles of metal react with 1 mol of O2(g); in the third, 4 moles of X react with 3 moles of O2(g)
So, lets probe those 3 cases.
3) Case 1: 1 mol of metal X / 1 mol O2(g) = x moles / 0.01226 mol
=> x = 0.01226 moles of metal X
Now you can calculate the atomic mass of the hypotethical metal:
1.15 grams / 0.01226 mol = 93.8 g / mol
That does not correspond to any of the metal with valence 1+
So, now probe the case 2.
4) Case 2:
2moles X metal / 1 mol O2(g) = x / 0.01226 mol
=> x = 2 * 0.01226 = 0.02452 mol
And the atomic mass of the metal is: 1.15 g / 0.02452 mol = 46.9 g/mol
That is similar to the atomic mass of titanium which is 47.9 g / mol and whose valece is 2+.
4) Case 3
4 mol meta X / 3 mol O2 = x / 0.01226 => x = 0.01226 * 4 / 3 = 0.01635
atomic mass = 1.15 g / 0.01635 mol = 70.33 g/mol
That does not correspond to any metal.
Conclusion: the identity of the metallic element could be titanium.
STEM is an acronym meaning
Science
Technology
Engineering
Mathematics
One of the main focuses of STEM courses is on science, so you will be learning about various types of science
This is an approach at learning to have students learn all four types of subjects in one class, based on real world applications.
Answer:
403 mL
Explanation:
First, I will assume that the mole is 1, because you are not specifing this.
Now, with the innitial data, we need to get the pressure:
T = 65+273 = 338 K
V = 500 / 1000 = 0.5 L
Now if:
PV = nRT
Then:
P = nRT/V and V = nRT/P
Let's calculate the P:
P = 1 * 0.082 * 338 / 0.5 = 55.432 atm
The standard temperature is 0° C or 273 K so, the volume is:
V = 1 * 0.082 * 273 / 55.432
V = 0.40384 L or simply 403.84 mL
