Explain why Cu 2 + is paramagnetic but Cu + is diamagnetic. (atomic number of Cu = 29 )

Magnetic nature and moment depends on the number of the unpaired electrons. As we can see there is no unpaired electron, so Cu + is diamagnetic. There is one unpaired electron in d orbital, so Cu + 2 is paramagnetic.

Which trivalent ion has a maximum size in the Lanthanoid series i.e., Lanthanum ion ( La + 3 ) to Lutetium ion ( Lu 3 + )? (atomic number of Lanthanum = 57 and Lutetium = 71 )

The Lanthanoid series starts from La and thus La + 3 will have the largest size because we know on moving across the period from left to right the size decreases in Lanthanoid and thus the same will be similar for the trivalent ions.

Complete and balance the following reaction: KMnO 4 + SO 2 + H 2 O → _______ + _______ + ________ .

Permanganate ion reacts with sulphur dioxide gas in acidic medium to produce Mn + 2 and hydrogensulphate ion. 2 KMnO 4 + 5 SO 2 + 2 H 2 O → K 2 SO 4 + 2 MnSO 4 + 2 H 2 SO 4

Complete and balance the following reaction: NaCl + MnO 2 + H 2 SO 4 → _______ + _______ + ________ + _____.

A balanced chemical equation occurs when the number of the different atoms of elements in the reactants side is equal to that of the products side. Manganese(IV) oxide react with sodium chloride and sulphuric acid to produce manganese(II) sulphate, chlorine, sodium sulphate and water. 2 NaCl + MnO 2 + 3 H 2 SO 4 → 2 NaHSO 4 + MnSO 4 + Cl 2 + 2 H 2 O

Complete and balance the following chemical equation: KMnO 4 + H 2 SO 4 + FeSO 4 → _____ + ______ + ______ + _______.

An important oxidising reaction of KMnO 4 are given below: In acid solution, Fe 2 + ion (green) is converted to Fe 3 + (yellow). 2 KMnO 4 + 8 H 2 SO 4 + 10 FeSO 4 → 5 Fe 2 ( SO 4 ) 3 + 2 MnSO 4 + K 2 SO 4 + 8 H 2 O