A homogeneous mixture has the same uniform appearance and composition throughout. A heterogeneous mixture consists of visibly different substances or phases. Homogeneous mixtures
So the answer is heterogeneous.
The only liquid elements at standard temperature and pressure are bromine (Br) and mercury (Hg). Although, elements caesium (Cs), rubidium (Rb), Francium (Fr) and Gallium (Ga) become liquid at or just above room temperature.
<h2>
Answer:</h2>
44.06 g/mol
<h3>
Explanation:</h3>
We are given;
- Number of moles of unidentified gas as 1.674×10^-4 mol
- Time of effusion of unidentified gas 86.6 s
- Number of moles of Argon gas as 1.715×10^-4 mol
- Time of effusion of Argon gas is 84.5 s
We are supposed to calculate the molar mass of unidentified gas
<h3>Step 1: Calculate the effusion rates of each gas</h3>
Effusion rate = Number of moles/time
Effusion rate of unidentified gas (R₁)
= 1.674×10^-4 mol ÷ 86.6 s
= 1.933 × 10^-6 mol/s
Effusion rate of Argon gas (R₂)
= 1.715×10^-4 mol ÷ 84.5 sec
= 2.030 × 10^-6 mol/s
<h3>Step 2: Calculate the molar mass of unidentified gas</h3>
- Assuming the molar mass of unidentified gas is x;
- We can use the Graham's law of effusion to find x;
- According to Graham's law of diffusion;

But, Molar mass of Argon is 39.948 g/mol
Therefore;


Solving for X
x = 44.06 g/mol
Therefore, the molar mass of the identified gas is 44.06 g/mol
She would divide that mass of each element by it molar mass the answer is C <span />