Answer:
A. Because they are compounds, they cannot be pure substances.
Explanation:
The false statement from the given choices is that because they are compounds they cannot be pure substances. In fact, because they are compounds they are pure substances.
Pure substances are made up of elements and compounds and they have the following properties:
- All parts are the same throughout
- Composition is definite
- They cannot easily be separated or broken
- Separation by physical method is not easy
- They have unique sets of physical and chemical properties.
<h2><em>Al2 S3</em></h2>
<em><u>The formula for aluminum sulfide is Al2 S3.</u></em>
<h2><em>hope it helps</em><em>!</em></h2>
Unlike nuclear reactions, nuclear reactions are not affected by changes in temperature,
pressure, of the presence of catalysts. Also nuclear reactions of given radioisotope cannot be slowed down, speeded up, or stopped.
Answer: 11 g
Explanation:
Zn + 2HCl → ZnCl₂ + H₂
Number of moles of Zn:
Number of moles = 5 g / 65.38 g/mol
Number of moles = 0.08 mol
Number of moles of HCl :
Number of moles = 50 g / 36.5 g/mol
Number of moles = 1.4 mol
Compare the moles of both reactant with zinc chloride:
Zn : ZnCl₂
1 : 1
0.08 : 0.08
HCl : ZnCl₂
2 : 1
1.4 : 1/2×1.4 =0.7 mol
The number of moles of zinc chloride produced by Zn are less so it will limit reactants.
Mass of zinc chloride:
Mass = 0.08 mol × 136.3 g/mol
<u>Mass = 11 g</u>
H20, water has hydrogen bonding because of the H-O linkage. NH3 is a polar covalent compound and has also hydrogen bonding because of N-H bonding. CH4, methane is a non-polar covalent compound, hence the forces existing is London dispersion force.