13. Nt
14. St
15. St
16. At
17. Nt
Answer:
2.11 x 10²⁴ molecules.
Explanation:
- <em>It is known that every 1.0 mole of a molecule contains Avogadro's number of molecules (NA = 6.022 x 10²³).</em>
<em><u>Using cross multiplication:</u></em>
1.0 mole of H₂O contains → 6.022 x 10²³ molecules.
3.5 mole of H₂O contains → ??? molecules.
∴ 3.5 mole of H₂O contain = (3.5 mol)(6.022 x 10²³) = 2.11 x 10²⁴ molecules.
Answer: B) Particles can be filtered from a suspension.
Explanation: Colloids are solutions with particle size intermediate between true solutions and suspensions. They exhibit tyndall effect that is scattering of light.
Suspensions have large sized particles which settle when left undisturbed for sometime and thus can be filtered off easily.
The particle size in colloids is less and hence they do not settle under the effect of gravity.
A solution can be homogeneous in which the composition is uniform or heterogeneous in which is the composition is not uniform.