Double Displacement Reaction
An element from each of two compounds switch places.
Example: compound + compound ⇒ compound + compound
Chemical reactions are processes in which substances change into other substances. A chemical reaction takes place if one or more of these occur:
Color changes - Different combinations of molecules reflect light differently. A color change indicates a change in molecules.
Heat content changes- In all chemical reactions, the heat content of the reactants and the heat content of the products is never the same. Sometimes the difference is great and can be easily detected. At other times, the difference is slight and more difficult to detect.
Gas produced - Whenever a gaseous product forms in a liquid solution, bubbles can be seen. A colorless gas produced in a reaction of solids is much harder to detect.
Precipitate forms- Precipitates are insoluble products formed by a reaction taking place in a liquid solution. This insoluble product will eventually settle to the bottom, but might immediately appear by turning the clear solution cloudy.
Complete Question
A radio technician measures the frequency of an AM radio transmitter. The frequency is 14603 kHz . What is the frequency in megahertz? Write your answer as a decimal.
Answer:
The value is 
Explanation:
From the question we are told that
The frequency is 
Generally


=> 
=> 
Answer:
Explanation:
Magnetic field = permeability x turn density x current
Magnetic field = 0.22T
turn density = 4150 /1.6 = 2593.75 t/m
permeability : µ = k µ°
µ°= 4 π 10^-7
k = 1
I = 0.22 / 4 π 10^-7 * 2593.75 = 0.22 10^7 /32594 = 67.497 A
Answer:
Option D is the correct answer.
Explanation:
Since value of angular acceleration is constant, the body has only centripetal acceleration.
Centripetal acceleration

We have radius = 7.112 cm = 0.07112 m
Frequency, f = 1975 rpm = 32.92 rps
Angular frequency, ω = 2πf = 2 x π x 32.92 = 206.82 rad/s
Substituting in centripetal acceleration equation,

Option D is the correct answer.
When calculated energy transferred between objects use the definition of heat as