Electrons exist in specified energy levels surrounding the nucleus.
Answer:
B.) +6
Explanation:
To find the oxidation number of sulfur, we can assume the oxidation numbers of the other elements.
What I mean is, oxygen (O) always has an oxidation number of (-2). That being said, if there are 4 oxygen atoms, oxygen is contributing -8 overall. We also know that hydrogen generally has an oxidation number of (+1). Like before, if there are 2 hydrogens, it must be contributing +2.
If the overall molecule is neutral, we have to get these charges to balance out.
In essence, -8 + 2 + ? = 0?
If you combine the charges from oxygen and hydrogen, you are left with -6. Therefore, to make the molecule neutral, sulfur must have an oxidation number of +6.
If you don't wash the thermometer, residual NaOH will react with the HCl solution. This is a highly exothermic reaction and will change the temperature of the solution, and thus throw off your measurement.
The pH meter can only be used to differentiate between weak and strong acids providing that the concentrations are known. However, it is convenient to determine the concentration of an acid (or base) by titration.