Answer: 0.0345 sec
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
![Rate=k[H_3PO_4]^2](https://tex.z-dn.net/?f=Rate%3Dk%5BH_3PO_4%5D%5E2)
k= rate constant = 
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
for completion of 20 % of reaction



The time taken for the concentration of
to decrease to 20% to its natural value is 0.0345 sec
Answer:
1. Sound is a energy (mechanical)produced by vibrating objects and sound energy is movement of energy through particles.
2.Space occupied by the substance
3.<u>Propagation</u> of <u>Sound Wave</u> and <u>particles of the medium</u>
4.High-Frequency(Ultrasonic wave)
Explanation:
1.Sound is the form of energy which causes sensation of hearing to our ear.It is produce by vibrating objects. When the objects vibrate(to and fro motion) ,they pushes the particles of medium creating the region of high density called compression .When the particles moves backward ,they creates a region of low density called Rarefaction.This pattern repeats indefinitely.
2.Volume is the quantity of three dimensional space occupied by substances like solid,liquid and gases. The SI unit of volume is

In metric system unit of volume is liter
3. Longitudinal Waves: Waves in which displacement of the medium particles are parallel(in the same direction) to the propagation of wave.
Sound wave is longitudinal wave.Hence its particles moves in the same direction as the wave (energy)travel.
4.Frequency: The number of times sound wave passes a given point in one second.Its SI unit is Hertz(Hz).
Frequency of vibration decides the Pitch of the sound waves producing them.
A sound wave of High Pitch means it is oscillating rapidly(at high speed).These are also called Ultrasonic waves. These have frequency more than 20000 Hz. Human being can't hear ultrasonic waves.
In 1 mole of
, there are 3 moles of ions, 1 mole of Ca^{2+} and 2 mole of
.

Molar mass of
is 110.98 g/mol. Calculating number of moles from given mass as follows:

Thus, number of moles of ions will be
.
Since, 1 mole of any substance has
units of that substance where
is Avogadro's number.
Thus, 9.38 mol of ions will have
number of ions.
Therefore, total number of ions in 347 g of
is
.
<h2>It would have an effect very much like over inflating a balloon. The space inside the Dyson Sphere would be overfilled with energy and the Sphere would be assaulted by energy that exceeds it's capacity to reflect it.</h2>
Remember one thing controlled variables is something. In an experiment that you like and you want to remain the same in order for the science experiment to be good