Radius of Xenon = 1.3Ă—10â’8 cm Volume = 100 ml = 0.1 L Pressure P = 1.2 atm = 121.59 Kpa Temperature = 281 K R = Gas Constant = 8.31 J mol^-1 K^-1 Now find the number of atoms PV = nRT => n = PV / RT n = (121.59 x 0.1) / (8.31 x 281) = / 2335.11 = 0.0052 Number of atoms in a mole is same as Avogadro constant A, which is 6.02 x 10^23 particles. n = number of atoms= 0.0052 N = number of particles Avogadro constant A = 6.02 x 10^23 n = N/A => N = n x A = 0.0052 x 6.02 x 106^23 = 3.13 x 10^20 Volume of Xe atom which would be a sphere = (4/3) x pi x r^3 Volume = = (4/3) x 3.14 x (1.3Ă—10â’8)^3 = 9.2 x 10^-24 Volume occupied by these particles = n x Volume = 3.13 x 10^20 x 9.2 x 10^-24 = 0.00288 Fraction of volume will be = 0.00288 / 0.1 = 0.0288
Low pH = high acidity. HF has a very low pH, so when added to a solution, it will lower the pH of the solution and therefore make it more acidic. So the answer should be B.
Wavelength = 434nm = 434 x 10⁻⁹m planck's constant = <span>h= 6.626 x 10 ⁻³⁴ J E =? by using the formula; E = hc /</span>λ value for c is 3 x 10⁸ m/s E = (6.626 x 10 ⁻³⁴ J)(3 x 10⁸ m/s) / 434 x 10⁻⁹m E = 1.9878 x 10⁻²⁵ / 434 x 10⁻⁹m E = 4.58 x 10⁻¹⁹ joules
