To estimate the relative atomic mass of element X, we need to take into account both the mass numbers of the isotopes and their percentage abundance.

Here's how to do it:

1. Multiply the mass number of each isotope by its percentage abundance.
For isotope 69 X: 69 * 0.60 = 41.4
For isotope 71 X: 71 * 0.40 = 28.4

2. Add these two values together to get the estimated relative atomic mass.
41.4 + 28.4 = 69.8

So, the estimated relative atomic mass of element X is 69.8.

Therefore, the correct box to tick would be "Between 69.5 and 70.0".

Question

To estimate the relative atomic mass of element X, we need to take into account both the mass numbers of the isotopes and their percentage abundance.

Here's how to do it:

1. Multiply the mass number of each isotope by its percentage abundance. 
   For isotope 69 X: 69 * 0.60 = 41.4
   For isotope 71 X: 71 * 0.40 = 28.4

2. Add these two values together to get the estimated relative atomic mass.
   41.4 + 28.4 = 69.8

So, the estimated relative atomic mass of element X is 69.8.

Therefore, the correct box to tick would be "Between 69.5 and 70.0".

Knowee AI · Accepted Answer

To estimate the relative atomic mass of element X, we need to take into account both the mass numbers of the isotopes and their percentage abundance.

Here's how to do it:

1. Multiply the mass number of each isotope by its percentage abundance. 
   For isotope 69 X: 69 * 0.60 = 41.4
   For isotope 71 X: 71 * 0.40 = 28.4

2. Add these two values together to get the estimated relative atomic mass.
   41.4 + 28.4 = 69.8

So, the estimated relative atomic mass of element X is 69.8.

Therefore, the correct box to tick would be "Between 69.5 and 70.0".

lement X has two isotopes. Their mass numbers are 69 and 71 The percentage abundance of each isotope is: • 60% of 69 X • 40% of 71 X Estimate the relative atomic mass of element X. [1 mark] Tick one box. < 69.5 Between 69.5 and 70.0 Between 70.0 and 70.5 > 70.5