The answer is definitely not 70.923
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:
Answer: The sample of wine could be described as numbers 1, 3 & 4
Explanation:
It is a mixture because it is the physical combination of two or more substances
It is a homogeneous mixture because any solid, liquid, or gaseous mixture that has the same proportions of its components throughout any given sample is regarded as a homogeneous mixture
It is a solution because it is a special type of homogeneous mixture composed of two or more substances
A chemical reaction happens when the atoms or molecules rearrange to form a new substance
<span>Cellular respiration is the chemical reaction in which glucose and oxygen are turned into water, carbon dioxide, and energy. Now you know the answer. :P</span>