You need to know the energy frequency relationship for photons, which is thanks to Max Planck:
Photon Energy = Planck constant x Frequency
Rarranged:
Photon Energy / Planck Constant = Frequency
Planck Constant = 6.63x10^-34
2.93x10^-25 / 6.63x10^-34 = Frequency
First shell from the nucleus can have a maximum of 2 electrons ! hope this helped
Answer: PbCO
Explanation: its quite simple really, you need to get a periodic table and find the symbol of said elements. Lead is Pb, and carbonate is another word for carbon and oxygen, so it is C and O
<span>A reversible reaction is a chemical change in which the products can be converted back to the original reactants under suitable conditions.</span><span> In a reversible reaction, changing the reaction conditions e.g. concentration, pressure or temperature will change the net direction the reaction goes i.e. more to the right (forward) or more to left (backward).<span>It also means a reversible reaction does not go to completion in either direction and all components, original reactants or ensuing products, ALL co-exist in the reaction mixture (see notes on chemical equilibrium).</span></span><span><span>This means the reaction can go in either direction i.e.</span><span> <span>A + B ==> C + D or C + D ==> A + B</span></span></span><span><span>A reversible reaction is shown by the sign ,</span><span> <span>a half-arrow to the right (direction of forward reaction), </span><span>and a half-arrow to the left (direction of backward reaction).</span><span>It is really important you understand that the terms right & left AND forward & backward are used in the context of how the equation is presented.</span></span></span><span><span>Most reactions are not reversible (irreversible) and have the usual complete arrow only pointing to the right.</span>
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Answer: gas are well separated with no regular arrangement.
liquid are close together with no regular arrangement.
solid are tightly packed, usually in a regular pattern.
its just gas liquid and solid pls make me brainliest
Explanation: