Which one of the following equations does not correctly represent the first law of thermodynamics for the given processes involving an ideal gas? (Assume non-expansion work is zero)

Which of the following amines can be prepared by Gabriel phthalimide reaction ?

The quantum number of four electrons are given below :
n = 4, l = 2, m_l =–2, m_s = –1/2
n = 3, l = 2, m_l = 1, m_s = +1/2
n = 4, l = 1, m_l = 0, m_s = +1/2
n = 3, l = 1, m_l = 1, m_s = –1/2
The correct order of their increasing enegies will be :

In order to oxidise a mixture of one mole of each of FeC₂O₄, Fe₂(C₂O₄)₃, FeSO₄ and Fe₂(SO₄)₃ in acidic medium, the number of moles of KMnO₄ required is :