When copper reacts with dilute nitric acid, gaseous nitrogen monoxide is formed as shown by the following equation. 



a Cu + b HNO[sub]3[/sub] = d Cu(NO[sub]3[/sub])[sub]2[/sub] + e H[sub]2[/sub]O + f NO



Which numbers are correct referring to a,b,d,e,f ?

We suppose during this task, that sulfuric acid (H[sub]2[/sub]SO[sub]4[/sub]) is a fully strong acid. What volume of a 0.0025M sulfuric acid solution has the same pH as 200,0 mL of 0,0050 M hydrochloric acid? Choose the best answer.

Calculate the mass of phosphorus required to make 12,25 m[sup]3[/sup] of standard state (T=298,16 K; p=760 Hgmm) phosphine gas (PH[sub]3[/sub]), by the reaction:



P[sub]4/s/[/sub] + 3 NaOH[sub]/aq/[/sub] +3 H[sub]2[/sub]O[sub]/l/[/sub] = 3 NaH[sub]2[/sub]PO[sub]4[/sub]/[sub]aq/[/sub] + PH[sub]3/g/[/sub]





(A[sub]r[/sub] (P): 31,0); (standard state molecular volume of ideal gases: 24,50 L/mol)

Gliders can be launched with a winch situated on the ground. The winch pulls a rope that is attached to the glider. Figure 1 shows the forces acting on the glider at one instant during the launch. The combined weight of the glider and pilot is 6500 N. 

[i]Calculate the angle between this resultant force (cca. 6083N) and the horizontal.[/i]



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