Answer:
- Question 19: the three are molecular compounds.
Explanation:
<em>Question 19.</em>
All of them are the combination of two kinds of different atoms in fixed proportions.
- C₂H₄: two carbon atoms per four hydrogen atoms
- HF: one hydrogen atom per one fluorine atom
- H₂O₂: two hydrogen atoms per two oxygent atoms
Thus, they all meet the definition of compund: a pure substance formed by two or more different elements with a definite composition.
Molecular compounds are formed by covalent bonds and ionic compounds are formed by ionic bonds.
Two non-metal elements, like H-F, C - C, C - H, H-O, H - H, and O - O will share electrons forming covalent bonds to complete their valence shell. Thus, the three compounds are molecular and not ionic.
<em>Question 20. </em>Formula of copper(II) sulfate hydrate with 36.0% water.
Copper(II) sulfate is CuSO₄. Its molar mass is 159.609g/mol
Water is H₂O. Its molar mass is 18.015g/mol
Calling x the number of water molecules in the hydrate, the percentage of water is:

From which we can solve for x:

Thus, there are 5 molecules of water per each unit of CuSO₄, and the formula is:
There are 137 atoms in this molecule. C55 + H72 = 127. 127 + Mg (one atom of magnesium = 128. 128 + N4 = 132. 132 + O5 = 137.
Answer:
volume = 13097674418.528dm³
Explanation:
n = (3.52)*10^32/(6.02)*10^23)
n = (584717607.97)
n = volume /molar volume
molar volume at stp = 22.4dm³
volume= 584717607.97 x 22.4
volume = 13097674418.528dm³
The exposure of a person to colloids majorly present in industrial area may results in the accumulation in the body tissue which causes dark deposit in the skin. They are not safe and is dangerous for health which may cause turning of skin blue permanently and it is life long.
Whereas, the colloid of silver nitrate is used to treat skin burns and ulcers but its overuse may result in adverse effect.
The answer is False ... Anyone can benefit form <span>scientific knowledge. Thank about your Health</span>