Answer:
B
Explanation:
Recall the law of effusion:

Because 5 mol of oxygen was effused in 10 seconds, the rate is 0.5 mol/s.
Let the rate of oxygen be <em>r</em>₁ and the rate of hydrogen be <em>r</em>₂.
The molecular weight of oxygen gas is 32.00 g/mol and the molecular weight of hydrogen gas is 2.02 g/mol.
Substitute and solve for <em>r</em>₂:

Because there are 5 moles of hydrogen gas:

In conclusion, it will take about 2.5 seconds for the hydrogen gas to effuse.
Check: Because hydrogen gas is lighter than oxygen gas, we expect that hydrogen gas will effuse quicker than oxygen gas.
Answer:
3) The calculated density would be high, because the volume would be incorrectly measured low.
Explanation:
Density is defined as mass per unit volume. It means the density is inversely proportional to the volume.
A solid with a hollow center will have high volume due to air inside the hollow area that will lead to low density.
But the error in the calculation of density is that the "density would be high, because the volume would be incorrectly measured low."
Hence, the correct answer is "3)"
Answer:
Its right you dont have to change anything
Answer:
Exothermic reaction
Explanation:
Since in an exothermic reaction heat is released, the products will be more stable than the reactants.
When cohesive force is stronger than the adhesive force: concave up meniscus, water forms droplets on surface