Answer:
Explanation:
In this problem, we need to convert 
to km².
We know that,
1 km = 1000 m
⇒ 1 km² = 10⁶ m²
So,
So, is equal to .
Answer : The concentration of NaOH is, 0.336 M
Explanation:
To calculate the concentration of base, we use the equation given by neutralization reaction:
where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:
Putting values in above equation, we get:
Thus, the concentration of NaOH is, 0.336 M
Phenolphthalein
In acid it is colourless and in water also colourless
Since obliquity is the angle between the axis of rotation and the direction perpendicular to the orbital plane, it changes as the orbital plane changes due to the influence of other planets. But the axis of rotation can also move (axial precession), due to torque exerted by the sun on a planet's equatorial bulge.
(Got it from google )
Atomic radius defines the size of an atom.
Explanation:
Atomic radius is defined as “one-half the distance between the nuclei of two identical atoms that are bonded together.” If ‘r’ is the atomic radius and ‘d’ the distance in between nuclei of two atoms that are identical and bonded, then r = d/2.
The units used to express atomic radius are picometer, nanometer, and Angstroms.
In the periodic table, the atomic radius of elements decreases with elements across a <em>period</em> (left-right) and increases with elements down a group.
