Answer: a) 
b) 
Explanation: Visible light is a form of electromagnetic wave.
Wavelength is defined as the distance between two successive crests of a wave. It is represented as symbol 
.
Frequency is defined as the number of complete cycles happening per second. It is represented by the symbol 
.
Wavelength and Frequency follow inverse relation,
where, c = speed of light = 
Wavelength and frequency of a wave is usually expressed in a range.
a) 
b) 
An H atom is made up of a nucleus with a +1 charge, as well as a single electron. Therefore, the only positively charged ion possible has charge +1.
I hope this helps!
The three word of this is to represent what it takes to create and maintain a fire
Answer:
CaS
Explanation:
calcium is Ca2+ and sulfur is S2- because the charges are equal you only need one of each atom, so the answer is CaS
Answer: -112200J
Explanation:
The amount of heat (Q) released from an heated substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Since,
Q = ?
Mass of water vapour = 30.0g
C = 187 J/ G°C
Φ = (Final temperature - Initial temperature)
= 100°C - 120°C = -20°C
Then apply the formula, Q = MCΦ
Q = 30.0g x 187 J/ G°C x -20°C
Q = -112200J (The negative sign does indicates that heat was released to the surroundings)
Thus, -112200 joules of heat is released when cooling the superheated vapour.
