Answer:
Explanation:
Data provided as per the question below:-
Wavelength = 430.nm
The computation of the frequency of the light is shown below:-
Frequency = Velocity of light ÷ Wavelength
The Velocity of light = 
Wavelength = 430 nm = 
m
Frequency = 
=
Therefore for determining the frequency we simply applied the above formula.
Answer:
B. Ca(NO2)2
Explanation:
Ions (charged atoms) combine with one another to form stable ionic compounds. In this case, calicium ion (Ca2+) is said to react with NO2, which has a charge of -1 i.e. +1-1(2) = 1-2 = -1.
This means that calcium has a charge of +2 while nitrite ion has charge of -1, hence, when they combine, they exchange their charges, which become their subscript as follows:
Ca2+ + NO2- → Ca(NO2)2
Ca(NO2)2 is a stable ionic compound called calcium nitrite. Notice that it takes two atoms of NO2- to react with one atom of Ca2+.
Boiling point is the temperature at which a substance begins to change to a gas. Melting point is the temperature at which a substance begins to turn into a liquid. And freezing point is the temperature at which a substance begins turning into a solid.
Answer:
The heat at constant pressure is -3,275.7413 kJ
Explanation:
The combustion equation is 2C₆H₆ (l) + 15O₂ (g) → 12CO₂ (g) + 6H₂O (l)
= (12 - 15)/2 = -3/2
We have;
Where R and T are constant, and ΔU is given we can write the relationship as follows;
Where;
H = The heat at constant pressure
U = The heat at constant volume = -3,272 kJ
= The change in the number of gas molecules per mole
R = The universal gas constant = 8.314 J/(mol·K)
T = The temperature = 300 K
Therefore, we get;
H = -3,272 kJ + (-3/2) mol ×8.314 J/(mol·K) ×300 K) × 1 kJ/(1000 J) = -3,275.7413 kJ
The heat at constant pressure, H = -3,275.7413 kJ.
No, why? Cause if you're winding up the clock it's basically doing what it needs to do. So there's no need for batteries.. I hope my sad sentence make sense :p
