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3 edited title

# Ionic Size Doubt Why is the size of Al3+ less than that of Li+?

2 mainly math formatting, some grammar

Why is it so that the size of $${Al}^{3+}$$$$\ce{Al^{3+}}$$ is lesser than $${Li}^{+}$$ $$\ce{Li+}$$?

I'm a bit confused forabout this one as in Aluminium the aluminium(3+III) ion, there are is composed of 10 electrons and 13 protons, while in Lithium (+)the lithium ion, there are has only 2 electrons and 3 protons.

Electronic Configurationconfiguration of $${Al}^{3+}$$ will be$$\ce{Al^{3+}}$$ is $$1s^2 2s^2 2p^6$$$$\mathrm{1s^2 2s^2 2p^6}$$ and that of $${Li}^{+}$$ will be $$1s^2$$$$\ce{Li+}$$ is $$\mathrm{1s^2}$$. Now

Now,doesn't this seem much it seems obvious that the size of $${Al}^{3+}$$$$\ce{Al^{3+}}$$ should be greater than that of $${Li}^{+}$$$$\ce{Li+}$$, but only the inverseit is true of thisactually the other way around. Why is it so?Why is this? I think that it is a kind of exception, but if any oneanyone can explain the reason behind this, it will help me in my upcoming Teststests.

Why is it so that the size of $${Al}^{3+}$$ is lesser than $${Li}^{+}$$ ?

I'm a bit confused for this one as in Aluminium (3+) ion, there are 10 electrons and 13 protons while in Lithium (+) ion, there are only 2 electrons and 3 protons.

Electronic Configuration of $${Al}^{3+}$$ will be $$1s^2 2s^2 2p^6$$ and that of $${Li}^{+}$$ will be $$1s^2$$ . Now,doesn't this seem much obvious that the size of $${Al}^{3+}$$ should be greater than that of $${Li}^{+}$$ but only the inverse is true of this. Why is it so? I think that it is a kind of exception, but if any one can explain the reason behind this, it will help me in my upcoming Tests.

Why is it so that the size of $$\ce{Al^{3+}}$$ is lesser than $$\ce{Li+}$$?

I'm a bit confused about this one as the aluminium(III) ion is composed of 10 electrons and 13 protons, while the lithium ion has only 2 electrons and 3 protons.

Electronic configuration of $$\ce{Al^{3+}}$$ is $$\mathrm{1s^2 2s^2 2p^6}$$ and that of $$\ce{Li+}$$ is $$\mathrm{1s^2}$$.

Now, it seems obvious that the size of $$\ce{Al^{3+}}$$ should be greater than that of $$\ce{Li+}$$, but it is actually the other way around. Why is this? I think that it is a kind of exception, but if anyone can explain the reason behind this, it will help me in my upcoming tests.

Why is it so that the size of $${Al}^{3+}$$ is lesser than $${Li}^{+}$$ ?
Electronic Configuration of $${Al}^{3+}$$ will be $$1s^2 2s^2 2p^6$$ and that of $${Li}^{+}$$ will be $$1s^2$$ . Now,doesn't this seem much obvious that the size of $${Al}^{3+}$$ should be greater than that of $${Li}^{+}$$ but only the inverse is true of this. Why is it so? I think that it is a kind of exception, but if any one can explain the reason behind this, it will help me in my upcoming Tests.