Acarbonatomhasarelativeatomicmassof12.7.60%ofthecarbonatomhasamassnumberof12.3.30%ofthecarbonatomshaveamassnumberof13.2,whilsttheremaining10%haveamassnumberwhichisnotknown.Calculatethemassnumberofthecarbonisotopewhichis10%oftheCarbon12.7atom.Giveyouranswerto1decimalplace,ifneeded.

The question is asking for the mass number of the carbon isotope that makes up 10% of the Carbon 12.7 atom.

First, let's break down the information given:

• 60% of the carbon atom has a mass number of 12.3
• 30% of the carbon atom has a mass number of 13.2
• The remaining 10% have a mass number which is not known.

The relative atomic mass of the carbon atom is given as 12.7. This is calculated as the sum of the products of the percentage abundance and the mass number of each isotope.

So, we can set up the following equation:

(0.60 * 12.3) + (0.30 * 13.2) + (0.10 * x) = 12.7

Where x is the mass number of the unknown isotope.

Solving for x gives:

x = (12.7 - (0.60 * 12.3) - (0.30 * 13.2)) / 0.10

Calculating the above expression gives:

x = 14.7

So, the mass number of the carbon isotope which is 10% of the Carbon 12.7 atom is 14.7.