In the series Sc(Z = 21) to Zn(Z =30), the enthalpy of atomisation of zinc is lowest i.e., `126 kJ mol^-1`.. Why ?

In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomisation of zinc is the lowest, i.e., 126 kJ moI^-1 . Why?

in 3d-series,zinc (Z=30) has highest enthalpy of atomisation.

Why do the transition elements have higher enthalpies of atomisation? In 3d series (Sc to Zn), which element has the lowest enthalpy of atomisation and why?

Calculate the enthaply change in the reaction, CH_(4)(g) + 2O_(2)(g) to CO_(2)(g) + 2H_(2)O (i)The enthalpy change of formation of CH_(4) (g), CO_(2)(g) and H_(2)O (i) are - 74.8 kj mol^(-1), -393.5 KJ mol^(-1) and - 286 KJ mol^(-1) respectively.

At 25^(@)C , when 1 mole of MgSO_(4) was dissolved in water, the heat evolved was found to be 91.2 kJ. One mole of MgSO_(4) . 7H_(2)O on dissolution gives a solution of the same composition accompanied by an absorption of 13.8 kJ. The enthalpy of hydration, i.e., DeltaH_(h) for the reaction MgSO_(4)(s) + 7H_(2)O(l)rarrMgSO_(4) . 7H_(2)O(s) :

Scandium (z = 21) is a transition element but zinc (z = 30) is not. Explain.

The amplifiers X, Y and Z are connected in series. If the voltage gains of X, Y and Z are 10, 20 and 30, respectively and the input signal is 1 mV peak value, then what is the output signal voltage (peak value) if d.c. supply voltage is 10V?

The amplifiers X, Y and Z are connected in series. If the voltage gains of X, Y and Z are 10, 20 and 30, respectively and the input signal is 1 mV peak value, then what is the output signal voltage (peak value) if d.c. supply voltage is 5V?

The first ionisation enthalpy (Delta_(i)H) values of the third-period elements, Na, Mg and Si are respectively 496, 737 and 786 kJ mol^(-1) . Predict whether the first Delta_(i)H value for Al will be more close to 575 or 760 kJ mol^(-1) . Justify your answer.