Answer:
The number of neutrons present in one atom of isotope of Silicon of mass 28 amu is<u> 14 neutrons</u>
Explanation:
Symbol of Si isotope

<u>Number of Neutron = Mass number - Atomic Number</u>
Mass number = Total number of protons and neutrons present in the nucleus of the atom.For Si = 28 amu
Atomic Number = Total number of Protons present in the nucleus.
Si = 14
Number of neutron = 24 - 14
= 14
Answer:
41.3kJ of heat is absorbed
Explanation:
Based in the reaction:
Fe₃O₄(s) + 4H₂(g) → 3Fe(s) + 4H₂O(g) ΔH = 151kJ
<em>1 mole of Fe3O4 reacts with 4 moles of H₂, 151kJ are absorbed.</em>
63.4g of Fe₃O₄ (Molar mass: 231.533g/mol) are:
63.4g Fe₃O₄ × (1mol / 231.533g) = <em>0.274moles of Fe₃O₄</em>
These are the moles of Fe₃O₄ that react. As 1 mole of Fe₃O₄ in reaction absorb 151kJ, 0.274moles absorb:
0.274moles of Fe₃O₄ × (151kJ / 1 mole Fe₃O₄) =
<h3>41.3kJ of heat is absorbed</h3>
<em />
Given: wavelength of Nitrogen laser (∧) = 337.1 nm = 337.1 X 10^-9 m
We know that, Energy of photon (E) = hc/∧ = hv
where, v = frequency of photon and c = speed of light = 3 X 10^8 m/s
Thus, v = c/∧ = (3 X 10^8)/ (337.1 X 10^-9) = 8.899 X 10^14 s-1.
Answer: F<span>requency of nitrogen laser = </span>8.899 X 10^14 s-1.