Any Chem AS question to be posted here :):)

[AS-Girl]

thanks tmisterr!
The answer for the first question is C..but it's not exactly the same answer i got..so u r probably right


I did it in an easier way
this was my way
p[H+] + p[OH-]=14
4.5 + x= 14
x=9.5

so i replaced all the values given in the equation -log[oh] =9.5
C was the only one close to 9.5..so predicted it was the answer!

[Haaks18]

There is a question which says Na,Na+,Mg,Mg+2,Cl,Cl- Arrange in order of the largest radius first and the smallest last

Another question says :D Arrange in order of polarising power..strongest first..Na+,Mg+2,Al+3 & K

Last Question  Arrange in order of the strongest bond first.. C-Cl, C-C and C-Br

Tada

[Amelia]

There is a question which says Na,Na+,Mg,Mg+2,Cl,Cl- Arrange in order of the largest radius first and the smallest last
Another question says :D Arrange in order of polarising power..strongest first..Na+,Mg+2,Al+3 & K
Last Question  Arrange in order of the strongest bond first.. C-Cl, C-C and C-Br
Tada

1) Cl^-, Cl, Mg²⁺, Na⁺, Mg, Na.
cations are smaller in size then there metal atoms, and anions are larger then their nonmetal atoms.

2) smaller size and greater charge creates high charge density and has the most polarizing power.
    Al³⁺, Mg²⁺, Na⁺, K⁺

3) C-C, C-Cl, C-Br.

[tmisterr]

1) Cl^-, Cl, Mg²⁺, Na⁺, Mg, Na.
cations are smaller in size then there metal atoms, and anions are larger then their nonmetal atoms.

2) smaller size and greater charge creates high charge density and has the most polarizing power.
    Al³⁺, Mg²⁺, Na⁺, K⁺

3) C-C, C-Cl, C-Br.

For 1 I disagree, I think it should be:
Na, Cl-, Mg, Cl, Na+, Mg2+

Since the are all in the same period they have the same number of energy levels, but as you move along the period, the nuclear charge increases so size of ATOMS get smaller, hence Na is the largest atom, then Mg then Cl. When it comes to ions, since Na+ and Mg2+ are bother losing an energy level so they only have 2 shells now. they will be the smallest, however Mg2+ has a higher nuclear charge so it will be smaller than Na+. for Cl-, it still has 3 energy levels since it has gained an electron to the third energy level. since nuclear charge is the same as Cl, it will be larger that a Cl atom, and even Mg atom, but smaller than Na+ since Na has a much smaller nuclear charge than Cl-

[Amelia]

For 1 I disagree, I think it should be:
Na, Cl-, Mg, Cl, Na+, Mg2+

Since the are all in the same period they have the same number of energy levels, but as you move along the period, the nuclear charge increases so size of ATOMS get smaller, hence Na is the largest atom, then Mg then Cl. When it comes to ions, since Na+ and Mg2+ are bother losing an energy level so they only have 2 shells now. they will be the smallest, however Mg2+ has a higher nuclear charge so it will be smaller than Na+. for Cl-, it still has 3 energy levels since it has gained an electron to the third energy level. since nuclear charge is the same as Cl, it will be larger that a Cl atom, and even Mg atom, but smaller than Na+ since Na has a much smaller nuclear charge than Cl-

You are right. It said largest radius first, I misread the question.
 Thanks for the correction.

[Haaks18]

Thaaanks you but isnt it Na and then Mg and then Cl- and then Cl and then Na+ and at last Mg+2?!

[Deadly_king]

Thaaanks you but isnt it Na and then Mg and then Cl- and then Cl and then Na+ and at last Mg+2?!

The answer is as follows:

Na, Cl^-, Mg, Cl, Na⁺, Mg²⁺

NOTE :
1. Leaving the noble gases out, atoms get smaller as you go across a period.

2. The ionic radii fall as you go across the period though we need to look at the positive and negative ions separately.

3. You're provided the exact length for the radii of these elements in the data booklet.

Click here for more notes about it.