Pure water may be identified by its density: it will have the lowwest density of the three solutions, given that the solutes (salt and sugar) increase the density (this is the easiests and quickest way).
You can also measure the freezing points or boling points to identify the pure water because the solutes depress the freezing points and increase the boling points.
To differentiate sugar water and salt water, you can probe which one conducts electricity, because salt water is a conductor (given that it ionizes into Na+ and Cl-) but sugar water is not a conductor.
The greenhouse effect is rightly called that because greenhouses allow heat to enter, but doesn't allow heat to leave, which warms plants.
On earth however, it's much bigger. Our own atmosphere acts similarly to this; it allows heat in, but doesn't allow it to leave which heats up the planet and causes global warming.
Assuming this is a true or false question, the answer would be True
<u>Answer:</u>
<u>A metallic bond is a force of attraction between charged metal ions and the electrons that are in the delocalized bond, which covers the assembly of ions. A covalent bond is the force of attraction between the nuclei of atoms, and the electrons shared between them.
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<u>Explanation:</u>
<u> A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond can be generated by electrostatic attraction between charged ions (for example, ionic bonds) or by electron sharing (for example, covalent bonds). </u>
I hope this helps you :)