The answer is H₃C₆H₅O₇ (OPTION D).
In essence, the question is asking which of the options is an acid or a neutral compound; thus not a base. A base is a compound that accepts free hydrogen ions while in aqueous solution and as such they usually lack hydrogen ions that can be released in solution. If you ionize all the compounds/molecules above, the only on that has free hydrogen ions is OPTION D (which is an organic acid and not a base).
Answer:
Nanomachines will work with atoms, not nuclei. The smallest unit of a chemical element, about a third of a nanometer in diameter. Atoms make up molecules and solid objects.
Explanation:
Au^2S^3+ 3H^2 = 2Au + 3H^2S

The Balanced equation will be :

The Coefficients are :
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Answer:
CCl4 - Nonpolar
CH3OH - polar
NH3 - polar
CS2 - Nonpolar
Explanation:
One important thing that we should know is that polarity has to do with the presence of a resultant dipole moment in a molecule.
Dipole moment is a vector quantity, This means that its direction is also taken into account when discussing the dipole moment of molecules.
Hence, symmetrical molecules such as CS2 and CCl4 are non-polar even though they have polar bonds because their dipoles cancel out(zero resultant dipole moment).
On the other hand, NH3 and CH3OH are non-symmetrical molecules hence they possess an overall dipole moment and are polar molecules.