[miss.strw]

For the following question use the general periodic trends you learned in class, not the experimental values from the figures in the text.

a) Which of the following elements has the largest first ionization energy?

    B  C  Be  N

b) Which of the following has the smallest atomic radius?

    C  Li  B  Be




You must enter both answers to the above questions with ONE and ONLY ONE space between each.
e.g., a correct answer format would be C Pb

I put
N Li

a) N
b) Li

But it is WRONG!!! What did I do wrong??? Plz tell me!!!

[UG]

The first one nitrogen is correct.
For the second one, what is the general trend for atomic radii as you move across a period?

[miss.strw]

The first one nitrogen is correct.
For the second one, what is the general trend for atomic radii as you move across a period?

As you move across the radii in the period gets bigger?
Since the order is Li, Be, B, C
Since it's asking for "smallest atomic radius? "
Shouldn't it be Li?

so for b) it suppose to be C ?   

Thank you, but please tell me if I am correct?

[UG]

As you move across the radii in the period gets bigger?

Now this is an incorrect statement, as you move across a period, the nuclear attraction gets larger because there are more protons, and the electrons are being added to the same major energy level (so they are not entering another energy level which is further away from the nucleus). The larger nuclear attraction 'pulls' the outer electrons closer towards the nucleus = smaller radii.

[UG]

so for b) it suppose to be C ?   

Thank you, but please tell me if I am correct?

Yes carbon has the smallest atomic radius.

[miss.strw]

As you move across the radii in the period gets bigger?

Now this is an incorrect statement, as you move across a period, the nuclear attraction gets larger because there are more protons, and the electrons are being added to the same major energy level (so they are not entering another energy level which is further away from the nucleus). The larger nuclear attraction 'pulls' the outer electrons closer towards the nucleus = smaller radii.

Thank you! I think I got confuse. I always think that when you get more electrons, the bigger raidus you have. Radius wif radii

[UG]

Just remember that it is the case when you go down a group, more electrons = larger radius since they are added to new energy levels further away from the nucleus and there is also more shielding from inner electrons, both of which reduces the effective nuclear charge on the outer electrons = larger radius.