The d- and f- B...

For $$Zn^{2+}$$, $$Ni^{2+}$$, $$Cu$$, and $$Cr^{2+}$$ which of the following statements is correct?

Transition elements form binary compounds with halogens. Which of the following elements will form $$MF_3$$ type compounds?

Choose the correct answer from the alternative given.
Amongst $$TiF_6^{2-}$$, $$CoF$$,   $$Cu_2$$ $$Cl_2$$ and $$NiCl$$, which are the colourless species? (atomic number of Ti = 22, Co = 27, Cu = 29, Ni = 28)

Colour of transition metal ions are due to absorption of some wavelength. This results in:

In the dichromate anion $$Cr_2O_7$$ :

Which of the following reactions do not result in the preparation of potassium dichromate from chromate?

(I) 4$$FeCr_2O_4$$ + 8$$Na_2CO_3$$+ $$7O_2$$$$\rightarrow$$

(II) $$Na_2CrO_4$$ + $$H_2SO_4$$ $$\rightarrow$$

(III) $$Na_2Cr_2O_7$$+ $$2KCl$$$$\rightarrow$$

Which of the following is not an actinide?

Which of the following catalysts is not correctly matched with the reaction?

Match the column I with column II and mark the appropriate choice.

Consider the following statements
I. $$La(OH)_3$$ is least basic among hydroxides of lanthanides.
II. $$Zr^{4+}$$ and $$Hf^{4+}$$ possess almost the same ionic radii.
III. $$Ce^{4+}$$ can act as an oxidizing agent.
Which of the above is/are true?