Becky's speed is her distance travelled which is 30 km divided by her time travelled of 2.5 hours which gives her average speed of 12 km/hour which is a quite good speed if she was say riding a bicycle and which would give her a good aerobic workout.
Answer:
To allow all the elements or compounds to separate complete.
Explanation:
In chromatography, the compounds need some space and time to separate, one from each other, if you just use the half of the paper strip maybe you will not notice the different spots of compounds. Remember all the substances have different affinity for the solvents, that means, some react very quickly but others need more time as the colors that conform the black color in an ink.
Yes, it is a Compound.
They both comprehend with the atoms of each sourse!
We will assume that the solvent is water. So, if we have 100 grams of the solution, 19 grams will be sodium hydroxide, while the remaining 81 grams will be water.
The molar weight of sodium hydroxide, NaOH, is 40. The molar weight of water is 18. Finding the moles of each:
NaOH:
19 / 40 = 0.475
Water:
81 / 18 = 4.5
Total moles present:
4.5 + 0.475 = 4.975 moles
The mole fraction of NaOH is:
0.475 / 4.975 = 0.0955
The mole fraction of NaOH is 0.0955
Answer:
Option-1 (O²⁻) is the correct answer.
Explanation:
All given anions contains same charge. So, we can ignore the effect of charge on these anions.
As we know all given compounds belongs to same group (Group 6) in periodic table. And from top to bottom along the group the elements are placed as,
Oxygen O
Sulfur S
Selenium Se
Tellurium Te
Hence, moving from top to bottom along the group the number of shells increases. And with increase in number of shell the atomic or ionic radii increases. As Oxygen is present at the top of the group, therefore, it has the smallest radius due to less number of shells.
