No and health

(1)① Ammonium chloride solid and calcium hydroxide solid react under the condition of heating to generate ammonia gas, so the reaction of device A is: 2NH4Cl+Ca(OH)2△. CaCl2+2NH3↑+2H2O，

So the answer is: 2NH4Cl+Ca(OH)2△. CaCl 2+2n H3 ↑+ 2H2O；

② Ammonia is an alkaline gas, which can be dried with alkaline lime. The function of alkali lime in device D is to remove water vapor from gas.

So the answer is: remove water vapor from the gas;

③ The concentrated ammonia in device C is volatile, which can produce ammonia. The experimental purpose can be achieved by removing device A,

Therefore, the answer is: concentrated ammonia is volatile, and nitrogen oxides will bring out ammonia when they enter device C;

(2)① According to the equation, NO can't be absorbed by itself, and the mixed gas of NO and NO2 is completely absorbed by NaOH solution, satisfying n (NO2): n (NO) ≥ 1. When n (NO2): n (NO) = 1, the minimum value of x is 2+ 12 = 65438.

So, the answer is: a;

② Limit method: if x= 1.5, the gas should be a mixture of NO and NO2, and the molar ratio of substances is 1: 1. The reaction is carried out according to type I, and there is no NO3-, and line A should represent NO2-;

By conservation method, the ratio of nitrogen to sodium in the reaction products of NaNO3 and NaNO2 is 1: 1, so it takes at least 0.5mol of sodium carbonate to completely absorb 1 mol of nitrogen oxides, and the calculated mass of sodium carbonate solution is 250g g.

So the answer is: NO2-; 250.