The seasons are caused as the earth, tilted on its axis, travels in a loop around the sun each year
The concentration of OH- ( symbol: [OH-] ), is equal to 10^-pOH (ten to the pOH'th power). The pOH equals 14 minus the pH, because the pH + the pOH = 14. So the pOH is 14-13= 1. Now the concentration of OH- is 10^-1 (= 1) moles/Litre
<span>NaOH (s) --> Na+ (aq) + OH- (aq) </span>
<span>1. : 1. : 1 </span>
<span>So by dissolving one mole of NaOH, you get one mole of Na+ and one mole of OH-. Meaning that the molarity (number of solved NaOH in one Litre) of NaOH is 1 mole/Litre, because the ratio is 1:1. This means, in ten litres of water there are also ten moles of NaOH. And the weight of one mole of NaOH is 40.00 grams (look it up in literature). So in ten litres solution with a pH of 13, there are 40.00*10 = 400 = 4 * 10^2 grams of NaOH dissolved</span>
ANSWER: We know, by law of constant proportion :
Chemical compounds always contains its component in constant fixed ratio or in fixed percentage without depend on its source, method of preparation and mass of compound.
Therefore, percentage of oxygen is same for any mass.
Hence, this is the required solution.
Explanation:
In my opinion, it is Ar (Argon)
Because as we move from left to right in a period, the value of ionization energy increases and Argon occupies the left most side in the respective period of the Periodic Table