C is the correct answer (CaF2) (sorry dont have subscript)
Explanation: synthesis reaction forms a compound and calcium reacting with fluorine produces Calcium Fluoride (CaF2) chemical name
Gold has a heavy enough nucleus that its electrons must travel at speeds nearing the speed of light to prevent them from falling into the nucleus. This relativistic effect applies to those orbitals that have appreciable density at the nucleus, such as s and p orbitals. These relativistic electrons gain mass and as a consequence, their orbits contract. As these s and (to some degree) p orbits are contracted, the other electrons in d and f orbitals are better screened from the nucleus and their orbitals actually expand.
Since the 6s orbital with one electron is contracted, this electron is more tightly bound to the nucleus and less available for bonding with other atoms. The 4f and 5d orbitals expand, but can't be involved in bond formation since they are completely filled. This is why gold is relatively unreactive.
Hope it helps
Answer : The percentage reduction in intensity is 79.80 %
Explanation :
Using Beer-Lambert's law :
where,
A = absorbance of solution
C = concentration of solution = 
l = path length = 2.5 mm = 0.25 cm
= incident light
= transmitted light
= molar absorptivity coefficient = 
Now put all the given values in the above formula, we get:
If we consider = 100
then, 
Here 'I' intensity of transmitted light = 20.198
Thus, the intensity of absorbed light 
= 100 - 20.198 = 79.80
Now we have to calculate the percentage reduction in intensity.
Therefore, the percentage reduction in intensity is 79.80 %
Answer:A
Explanation:For a given amount of solute, smaller particles have greater surface area. With greater surface area, there can be more contact between particles of solute and solvent.
