Calculate the percentage yield of the reaction if 64 g` NaBH_(4)` with iodine procuced 15.0 g of` BI_(3).
NaBH_(4) + 4I_(2) rarr BI_(3) + NaI + 4HI`

Complete the reaction: 4Al + 3O_2 rarr

Calculate the volume of 4.4 g of CO_2 at S.T.P.

Express the rate of the following reaction : 4PH_3 rarr P_4+ 6H_2

Calculate number of electron present in 9.5" g of" PO_(4)^(3-) :

Calculate the mass percentage of aspirin (C9H804) in acetonitrile (CH_3CN) when 6.5 g of C_9H_8O_4 is dissolved in 450 g of CH_3CN .

Calculate enthalpy of the reaction : 4NH_3(g) +3O_2(g) rarr 2N_2(g)+ 6H_2O (I) at 298K, given /_\H_f for , NH_3 (g) , H_2O (I) are - 46 k J / mol and -286 k J per mol respectively.

Calculate the standard enthalpy of reaction for the following reaction using the listed enthalpies of reaction : 3Co(s)+2O_(2)(g)rarrCo_(3)O_(4)(s) 2 Co(s)+O_(2)(g)rarr2CoO(s)," "DeltaH_(1)^(@)=-475.8 kJ 6CoO(s)+O_(2)(g)rarr2Co_(3)O_(4)(s),DeltaH_(2)^(@)=-355.0 kJ

Calculate the heat of formation of n butane from the following data: a. 2C_(4)H_(10)(g) +13O_(2)(g) rarr 8CO_(2)(g) +10H_(2)O(l), DeltaH = - 5757.2 kJ b. C(s) +O_(2) (g)rarrCO_(2)(g), DeltaH =- 405.4 kJ c. 2H_(2)(g) +O_(2)(g) rarr 2H_(2)O(l), DeltaH =- 572.4 kJ

Complete the following reaction : 4Al+ 3 O_2 rarr

Calculate the weight of iron which will be converted into its oxide (Fe3O4) by the action of 14.4g of steam on it.