Answer:
Besides electrical, chemical, and thermal energy, some other forms of energy include mechanical and sound energy. Any of these forms of energy can change into any other form. Often, one form of energy changes into two or more different forms.
See the correct answer is b.)PbS
D=m/v d=63.5g/11.6cm3=5.47g/cm3
Answer:
infrared waves are longer than gamma rays
Explanation:
according to the order :
radio, microwaves, infrared, light, ultraviolet, X-ray, gamma rays
radio waves have the highest wavelenght and lowest frequency, gamma rays have the highest frequency and lowest wavelength.
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

The equation can be written in terms of ions as:

Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.
The ions which are present on both the sides of the equation are potassium and nitrate ions and hence are not involved in net ionic equation.
Hence, the net ionic equation is :
