Question #d0a6c

1 Answer
Nov 20, 2017

Answer:

#""_17^37"Cl"#

Explanation:

For starters, take a look in the Periodic Table and find the atomic number of sulfur, #"S"#.

#Z_ "sulfur" = 16#

Since your unknown atom contains #1# more proton than the sulfur-36 isotope, which contains #16# protons inside its nucleus, you can say that you're dealing with the element that has

#Z = 16 + 1 = 17#

This element is chlorine, #"Cl"#, the element that follows sulfur in the Periodic Table.

Now, the number of neutrons present in the sulfur-36 isotope is given by the mass number of the isotope, #A#, and the atomic number of the element, #Z#.

#color(blue)(ul(color(black)("no. of neutrons" = "mass number " - " atomic number")))#

For the sulfur-36 isotope, you have

#{(A = 36), (Z = 16) :}#

This means that this isotope contains

#"no. of neutrons" = A - Z#

#"no. of neutrons" = 36 - 16 = 20#

You can thus say that the chlorine isotope, which contains the same number of neutrons as the sulfur-36 isotope, will have a mass number equal to

#A = Z + "no. of neutrons"#

#A = 17 + 20 = 37#

This means that the unknown isotope is chlorine-37, one of two stable isotopes of chlorine. In isotope notation, which uses the atomic number, the mass number, and the chemical symbol of the element

http://chemkjj.blogspot.ro/2015/06/c1-12-proton-number-mass-number-ions.html

you can represent chlorine-37 as

#""_17^37"Cl" -> {("mass number" = 37), ("atomic number" = 17) :}#