Answer:
The molar mass of the gas is 44 g/mol
Explanation:
It is possible to solve this problem using Graham's law that says: Rates of effusion are inversely dependent on the square of the mass of each gas. That is:

If rate of effusion of nitrogen is Xdistance / 48s and for the unknown gas is X distance / 60s and mass of nitrogen gas is 28g/mol (N₂):

6,61 = √M₂
44g/mol = M₂
<em>The molar mass of the gas is 44 g/mol</em>
<em></em>
I hope it helps!
The empirical formula for this vitamin : C₃H₄O₃
<h3>Further explanation
</h3>
The empirical formula is the smallest comparison of atoms of compound =mole ratio of the components
The principle of determining empirical formula
- Determine the mass ratio of the constituent elements of the compound.
- Determine the mole ratio by dividing the percentage by the atomic mass
Mass of C in CO₂ :(MW C = 12 g/mol, CO₂=44 g/mol)

Mass of H in H₂O :(MW H = 1 g/mol, H₂O = 18 g/mol)

Mass O = Mass sample - (mass C + mass H) :

mol ratio C : H : O =

b. o2
oxygen is diatomic because 1 molecule is made of 2 atoms of oxygen
Answer:
Li2S> Na2S> K2S> CsS
Explanation:
The lattice energy of ionic species depends on the relative sizes of ions in the ionic compounds. As the size of ions increases, the lattice energy decreases and vice versa.
When the size of the anions are the same, the lattice energy now depends on the relative sizes of the cations. Therefore, since all the compounds are sulphides and the order of magnitude of ionic sizes is: Li^+ < Na^+ < K^+ < Cs^+.
Therefore, the order of decrease in lattice energy is; Li2S> Na2S> K2S> CsS