<u>Answer:</u>
<em>Silver tarnishing as the silver metal reacts with sulphur is a chemical change.</em>
<u>Explanation:</u>
Tarnishing is the process of chemical change occurring on the surface of objects leading to corrosion or other defects on the surface. The remaining options like dilution, eroding is a physical change where the concentration of salt and rock particles will be decreased, respectively.
Similarly for soil drying also the concentration of water will be decreased leading to a physical change from wetty or dry soil.
But the last option which indicates tarnishing of silver metal on reaction with sulphur is a chemical process as the surface of silver metal will be reacting to sulphur and leads to lose of electrons which leads to corrosion of the surface or tarnishing of silver.
Its C
a catalyst speeds up a reaction by offering the reaction an alternative reaction pathway with a lower activation energy
hope that helps
Answer: The wavelength of the x-ray wave is 
Explanation:
To calculate the wavelength of light, we use the equation:
where,
= wavelength of the light = ?
c = speed of x-ray= 
= frequency of x-ray = 
Putting in the values:
Thus the wavelength of the x-ray wave is
The correct answer among the options given is B. . When
the forward and reverse paths of a change occur at the same rate, <span>the system is in equilibrium specifically in
dynamic equilibrium.<span> Dynamic equilibrium is
the balance in a process that is continuing. </span></span>
To get the concentration of the second solution let us use the following formulae
C1V1=C2V2 where C1 is concentration of first solution and V1 is the volume of solution first solution. on the other hand C2 is the concentration of second solution and V2 is the volume of second solution.
therefore
0.8×2=(2+10)×C2
1.6 =12×C2
1.6/12=C2
C2 = 0.1333mg/mL
