Answer:The visible light contains 7 colours : Violet, indigo, Blue, Green, Yellow, Orange and Red.
White colour is formed by the interference of all 7 colours, thus white light has the combination of all frequencies of visible light.
Explanation:
<span>The </span>standard enthalpy of formation<span> <span>is defined as the change in </span></span>enthalpy<span> <span>when one mole of a substance in the </span></span>standard<span> <span>state (1 atm of pressure and temperature of 298.15
K) is </span></span>formed<span> <span>from its
pure elements under the same conditions.</span></span>
Answer:
The speed of sound in hydrogen gas is 361.5 
Explanation:
It is given that the temperature is 50
.
The speed of sound in meter per second is calculated by an equation.
The equation states that speed of the sound in meter per second is equal to the sum of the product of the temperature in degree celsius with 0.60 and a constant that is 331.5.
The equation is written as:

Put the value of T = 50 then the equation becomes,

Speed of sound (in m/s) = 361.5 m/s
Answer is: 12,6% (1/8) <span>percentage of the sample will remain.
</span>c₀ - initial amount of C-14.<span>
c - amount of C-14 remaining
at time.
t = 5700</span> y.<span>
First calculate the radioactive decay rate constant λ:
λ = 0,693 ÷ t = 0,693 ÷ 5700</span> y = 0,000121 1/y = 1,21·10⁻⁴ y.
c = c₀·e∧-λ·t.
c = 2000 · e∧-(0,000121 1/y · 17100 y).
c = 252 g.
ω = 252 g ÷ 2000 g = 0,126 = 12,6%.
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