Answer is: molar mass
of compound is 154,58 g/mol.<span>
m(</span>naphthalene<span>) = 10 g = 0,01 kg.
m(unknown compound) = 1,00 g.
</span>Δ<span>T (solution) = 4,47 °C.
Kf(</span>naphthalene) = 6,91°C/m<span>; cryoscopic
constant.
M</span>(unknown compound) = Kf(naphthalene)· m(unknown compound) ÷
m(naphthalene)<span> · ΔT(solution).
M(xylene) = </span>6,91°C/m<span> · 1 g ÷ 0,01 kg · 4,47</span>°C<span>.
M(xylene) = 154,58 g/mol.</span>
If the reaction is
X + Y → Products
Then the rate is
R = k[X]ᵃ [Y]ᵇ
Where,
R = the rate of the reaction (mol L⁻¹ s⁻¹)
k = rate constant
[X] and [Y] = concentrations of the reactants (mol L⁻¹)
a = order of the reaction with respect to X
b = order of the reaction with respect to Y
overall reaction order, n = a + b
according to the given rate expression,
rate = [a][b]³
order of the reaction with respect to 'a' is 1
order of the reaction with respect to 'b' is 3
Overall reaction order = 1 + 3
= 4
Use the ideal gas law: PV = nRT, and solve for T,
T = PV/nR.
We should convert any of our parameters to units that would be easy to use with a known R value. One option would be to have the pressure in atm, volume in L, and convert the mass of the hydrogen gas to moles:
P = 1.2 atm
V = 750 mL = 0.750 L
n = (0.30 g H2)/(2.0159 g/mol) = 0.1488 mol H2
R = 0.0821 L•atm/mol•K.
Solving for T,
T = (1.2 atm)(0.750 L)/(0.1488 mol H2)(0.0821 L•atm/mol•K) = 73.671 K.
If you opt to leave your temperature in Kelvin, I would go with 74 K, as that has two significant figures like the rest of the values.
If you opt to go with Celsius, then the answer would be a bit awkward if you had to follow two sig figs: 73.671 - 273.15 = -199.49 ≈ -2.0 × 10² °C.
Pick your poison, I suppose.
Answer:
A)
.
Explanation:
An electronic configuration is an expression/ arrangement of the electrons in an atom or element. The principle of the orbitals are followed to write the electronic configuration of any atom or element.
At the ground state, the electrons in an atom or element are not excited, thus they are in their lowest energy state.
Manganese atom has 25 electrons, so its electronic configuration is
.
The principal factor for determining whether a nucleus is stable is the neutron to proton ratio. Elements with Z < 20 are lighter and these elements' nuclei and have a ratio of 1:1 and prefer to have the same amount of protons and neutrons.