Answer:
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- <em>19. C₂H₂, HF, and H₂O₂ are molecular compounds</em>
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- <em>20. The formula is CuSO₄. 5H₂O</em>
Explanation:
<u><em>Question 19.</em></u>
The three the chemical formulae in red, C₂H₂, HF, and H₂O₂, represent compounds because a compound is the chemical union of two or more atoms of different kind.
The chemical union is done either by ionic bonds or covalent bonds.
C, H, F, and O are all non-metal elements. Non-metals combine each other through covalent bonds, which is the bond in which electrons are shared to complete the valence shell. Ionic bonds are formed by the electrostatic atraction between ions of different charge and is typical of the bond between a metal and a non-metal.
Thus, all the bonds are covalent and the compounds are molecular compounds.
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<u><em>Question 20. </em></u>
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You can determine the chemical formula using the molar masses of both Copper(II) sulfate and water.
- Molar mass of copper(II) sulfate: 159.609 g/mol
- Molar mass of water: 18.015 g/mol
Call n the number of water molecules in the molecular formula:
The ratio of water to copper(II) sulfate is:
- n × molar mass of water / molar mass of the compound
- n × 18.015 / (n × 18.015 + 159.609) = 36%
- 18.015n = 0.36(18.015n + 159.609)
- 18.015n = 6.4854n + 57.45924
Therefore, the formula of the hydrate contains 5 molecules of water and it is CuSO₄.5H₂O.
The answer to this question would be: ammonia
Chemical decomposition is the breakdown of a compound into smaller compound or element. In this question, the Sodium(Na), Argon (Ar) and Sulfur(S) is elements, not compounds.
An element should not breakable since it was the simplest form.
Ammonia(NH3) is a compound so it should be able to be decomposed.
Answer:
the fastest would be gas, liquid would be in the middle and solid would be the slowest
Explanation:
Answer:
<em>C. The electron-withdrawing fluorine atoms pull electron density from the oxygen in trifluoroacetate. The negative charge is more stabilized in trifluoroacetate by this effect.</em>
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Explanation:
<em>The structures of trifluoroacetate and acetic acid are both shown in the image attached.</em>
<em>The trifluoroacetate anion (CF3CO2-), just like the acetate anion has in the middle, two oxygen atoms.</em>
<em>However, in the trifluoroacetate anion, there are also three electronegative fluorine atoms attached to the nearby carbon atom attached to the carbonyl, and these pull some electron density through the sigma bonding network away from the oxygen atoms, thereby spreading out the negative charge further. This effect, called the "inductive effect" stabilizes the anion formed,the trifouoroacetate anion is thus more stabilized than the acetate anion.</em>
<em>Hence, trifluoroacetic acid is a stronger acid than acetic acid, having a pKa of -0.18.</em>
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<u><em>Hope this helps!</em></u>
<u><em>Please mark brainliest!</em></u>
