Where is the rest of the question?
Answer:
8 to 1.
Explanation:
- Oxygen combines with hydrogen atoms to form water according to the balanced equation:
<em>O₂ + 2H₂ → 2H₂O.</em>
It is clear that one mole of oxygen combines with two moles of hydrogen atoms to form 2 moles of water.
So, the molar ratio of oxygen to hydrogen is (1 to 2).
- The mass of 1 mole of oxygen = (no. of moles)(molar mass) = (1 mol)(32.0 g/mol) = 32.0 g.
- The mass of 2 moles of hydrogen = (no. of moles)(molar mass) = (2 mol)(2.0 g/mol) = 4.0 g.
<em>So, the mass ratio of oxygen to hydrogen (32.0 g/4.0 g) = (8: 1).</em>
<em></em>
I think the correct answer is the first option. It has nonpolar bonds and a symmetrical structure. The structure of a BF3 molecule shows a symmetrical trigonal geometry. The net dipole moment of the molecule is zero therefore it is polar.
The whitening toothpastes showed differences in their physical-chemical properties. All toothpastes promoted changes to the surface, probably by the use of a bleaching agent.
