Phenolphthalein turn pink in basic solutions.it turn colourless in acid solution.
Hence options(1)is correct
<span>C. compounds that have the same atoms arranged in the same order, but with different three-dimensional orientations.</span>
Answer:
Option C
Explanation:
The answer is option C or "The amount of time it takes to rotate around it's axis is the same amount of time it takes to revolve around Earth."Remember that the Earth and the Moons amount of time to make a full rotation is almost in sync and they're two sides of the moon, one side we do not see and that's because that side is currently faced away from the Earth which is called the dark side of the moon. Each side has two weeks oh night, and two weeks of day because of how long it takes the moon to revolve, so while we have a side towards the Earth which is illuminated by the sun we have another pointing away in the dark.
Hope this helps.
Answer: (a) The solubility of CuCl in pure water is
.
(b) The solubility of CuCl in 0.1 M NaCl is
.
Explanation:
(a) Chemical equation for the given reaction in pure water is as follows.

Initial: 0 0
Change: +x +x
Equilibm: x x

And, equilibrium expression is as follows.
![K_{sp} = [Cu^{+}][Cl^{-}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5BCu%5E%7B%2B%7D%5D%5BCl%5E%7B-%7D%5D)

x = 
Hence, the solubility of CuCl in pure water is
.
(b) When NaCl is 0.1 M,
, 
, 
Net equation: 
= 0.1044
So for, 
Initial: 0.1 0
Change: -x +x
Equilibm: 0.1 - x x
Now, the equilibrium expression is as follows.
K' = 
0.1044 = 
x = 
Therefore, the solubility of CuCl in 0.1 M NaCl is
.
Answer: The correct option is The properties of a noble gas.
Explanation: There are 7 periods in the periodic table.
The last element of each period are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn) and Ununoctium (Uuo).
- The electronic configuration for Helium is
. For He, The outermost electrons are 2.
- The electronic configuration for all the other elements is
( where, n = 2, 3, 4, 5, 6 and 7 respectively). For all the other gases, the outermost electrons are 8.
All these elements have stable electronic configuration and are not reactive in nature. Hence, they are considered as noble gases.
Therefore, the last element of each period always have the properties of a noble gas.