Answer is: volume of helium is 244.72 liters.
m(He) = 43.7 g.
n(He) = m(He) ÷ M(He).
n(He) = 43.7 g ÷ 4 g/mol.
n(He) = 10.925 mol.
V(He) = n(He) · n(He).
V(He) = 10.925 mol · 22.4 L/mol.
V(He) = 244.72 L.
Vm - molar volume at STP.
n - amount of substance.
Atomic mass Ni = 58.69 a.m.u
58.69 g ----------------- 6.02x10²³ atoms
?? g --------------------- 7.5x10¹⁵ atoms
58.69x (7.5x10¹⁵) / 6.02x10²³
=> 7.31x10⁻⁷ g
The moles of chromium (iii) nitrate produced is calculated as follows
write the equation for reaction
3 Pb(NO3)2 + 2 Cr = 2 Cr(NO3)3 + 3 Pb
by use of mole ratio between Pb(NO3)2 to Cr(NO3)3 which is 3 : 2 the moles of Cr(NO3)3 is therefore
= 0.85 x2 /3 = 0.57 moles
The simplified solubility of glucose at 30°C is 1.25 g/g of water. Considering that the density of water at 30°C is 1 g/mL, the equivalent mass of 400 mL of water is also 400g.
The concentration of the solution in water is,
550 g/400g of water = 1.375 g glucose / g of water
Since the concentration is higher compared to the solubility of glucose at the specified temperature, it can be said that the solution is SATURATED.
