Answer:
they are composed of water
Answer:
Purpose: To become familiar with the techniques for separation of amixture of solids.
Explanation:
a mixture of pure substances. If you have a mixture of tennis ballsand marbles (not pure substances by the way), it would be easy toseparate the mixture. However, it is more difficult to separate asand (also not a pure substance) and salt mixture. Even with verygood tweezers and a magnifying glass, it would be extremelytedious. You could take advantage of the fact that salt dissolvesin water and sand does not. To separate iron powder from an ironand sand mixture you can take advantage of the magnetic propertiesof iron and separate the mixture.
To summarize a complete procedure for separating a mixture ofseveral substances, it is best to prepare a flow chart. A flowchartis a schematic representation of an algorithm or a stepwiseprocess, showing the steps as boxes of various kinds, and theirorder by connecting these with arrows. Flowcharts are used indesigning or documenting a process.
Answer:
c. CH4 < NH3 because the NH bond is more polar than the CH bond.
Explanation:
Actually, the electronegativity difference between carbon and hydrogen is just about 0.4. This meager difference in electronegativity corresponds to a nonpolar bond between the two atoms.
However, the electronegativity difference between nitrogen and hydrogen is about 0.9. This larger electronegativity difference corresponds to the existence of a polar covalent bond between the two atoms.
Hence the N-H bond is significantly polar unlike the C-H bond. This implies that CH4 molecules are only held together by weak dispersion forces while NH3 molecules are held together by stronger dipole-dipole interactions and hydrogen bonds.
