<span>The velocity of a wave is calculated by v = λf. From this equation we can take the frequency f = v / λ and substitute in the energy equation to find a new equation for the calculation of the energy from the wavelength:
E = hc / λ</span>
To calculate the photon energy, in eV (Electrovolt), when we have the value of the wavelength λ (necessarily given in Å - angstrom), we use an alternative equation given by:
Data: 670.8 Å
Solving:
Answer:
OD. 2HCl
Explanation:
A balanced equation needs the equal # of each element on BOTH sides.
By putting a 2 in front of HCl you now have 2 hydrogens on both sides and 2 chlorines. The Ca and CO3 are already balanced.
Answer:
protons
These particles do not vary in quality from one element to another; rather, what gives an element its distinctive identification is the quantity of its protons, called its atomic number. Protons and neutrons contribute nearly all of an atom's mass; the number of protons and neutrons is an element's mass number
Explanation:
hydrogen is the lightest element in the periodic table
If you mean what group of elements react the most, the answer is the alkali metals and the halogens because they both only either need to gain or lose one electron. If you mean the most reactive element, it would be fluorine because it has the most electronegativity.
