a) The percentage of presence in nature of 1st 2nd and 3rd isotopes is 92.2% 4.7 % and 3.1 %.
b) The chemical symbol for isotopes is ²⁸Si , ²⁹Si , ³⁰Si.
Element with atomic number 14 silicon . chemical symbol is Si.. Four isotopes of silicon's occur in natural environment- ²⁸Si , ²⁹Si , ³⁰Si ³²Si. The ²⁸Si , ²⁹Si , ³⁰Si is stable isotopes. And the fourth one ³²Si is radiogenic. Silicon atom have mass of 28 amu. ²⁸Si is the most abundant isotope of silicon has percentage of 92.2% . ²⁹Si is 4.7 % and the third is ³⁰Si is 3.1 %.
Thus, An unknown element Y with atomic number 14 is found in nature as a mixture of three isotopes. isotopes 28 has percentage of 92.2 % and isotopes 29 which has percentage of 4.7 %.the third isotopes is 30.
a) The percentage of presence in nature of 1st 2nd and 3rd isotopes is 92.2% 4.7 % and 3.1 %.
b) The chemical symbol for isotopes is ²⁸Si , ²⁹Si , ³⁰Si.
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