We first need to find the number of moles of gas in the container
PV = nRT
where;
P - pressure - 2.87 atm x 101 325 Pa/atm = 290 802.75 Pa
V - volume - 5.29 x 10⁻³ m³
n - number of moles
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 230 K
substituting these values in the equation
290 802.75 Pa x 5.29 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 230 K
n = 0.804 mol
the molar mass = mass present / number of moles
molar mass of gas = 56.75 g / 0.804 mol
therefore molar mass is 70.6 g/mol
Must be Selenium (Se). It is two space away from Kr, which means that it needs two extra electron to be like a noble gas, Kr.
Answer:
<em>By</em><em> </em><em>Bayer</em><em> </em><em>process</em><em>.</em>
Explanation:
<em>In the Bayer process, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution (caustic soda) at a temperature of 150 to 200 °C. At these temperatures, the aluminium is dissolved as sodium aluminate (primarily [Al(OH)4]−) in an extraction process.</em>
The reaction is:
X + Y → W + Z
Chemical energy of reactant X = 199.3 J = Ux
Chemical energy of reactant Y = 272.3 J = Uy
Chemical energy of Product W = 41.9 J = Uw
Chemical energy of Product Z = ? = Uz
Where reaction loses energy = 111.6 J = ΔU
By using the equation:
(Ux + Uy) – (Uw + Uz) = ΔU
Ux + Uy – Uw – Uz = ΔU
Uz = Ux + Uy – Uw –ΔU
Uz = 199.3 + 272.3 – 41.9 – 111.6
Uz = 318.1 J
Product Z must contain 318.1 J chemical energy.
