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  An ion has 12 protons, 14 neutrons, and  10 electrons. The symbol for the ion is      

A pulse of light beam contains 6.022×1022 photons of wavelength of 102.5nm. What is the total energy of this pulse of light beam (in J)? Mark your answer next to words “Final answer is”. You must follow significant figure rules.   You must show your work here to receive any credit (you may receive 0 points for only showing your final answer).

Choose the ground state electron configuration for Ti2⁺.    

Place the following in order of increasing atomic radius. As F Br    

Place the following in order of increasing IE1. N F As    

The ionization energies of an unknown third-period element are shown below. Identify the element. IE1 = 578 kJ/mol IE2 = 1820 kJ/mol IE3 = 2750 kJ/mol IE4 = 11600 kJ/mol IE5 = 14800 kJ/mol

An unknown element has two naturally occurring isotopes with masses 48.93 amu (A) and 50.92 amu (B) and has an atomic mass of 49.72 amu.  What’s the natural abundance of isotope A (%)?  Mark your answer next to words “Final answer is”. You must follow significant figure rules.   You must show your work here to receive any credit (you may receive 0 points for only showing your final answer).

A solid gold cube contains 4.65×1021 atoms.  What is the volume of the cube in cm3? The density of gold is 19.3 g/cm3. Mark your answer next to words “Final answer is”. You must follow significant figure rules.   You must show your work here to receive any credit (you may receive 0 points for only showing your final answer).

I dont know man just do what you must

Which of the following dental instruments is used to contour a matrix band?