Question

QUESTION 1 The formula mass of ammonium phosphite, (NH 4) 3PO 3, is a. 153.11 amu O b. 125.01 amu c. 97.01 amu d. 133.09 amu QUESTION 2 Naturally occurring element X exists in three isotopic forms: X-28 (27.977 amu, 92.23% abundance), X-29 (28.976 amu, 4.67% abundance), and X-30 (29.974 amu, 3.10% abundance). Calculate the atomic weight of X. a. 27.16 amu b.28.97 amu O c. 86.93 amu d. 48.63 amu e. 28.09 amu QUESTION 3 Balance the following equation in standard form and determine the sum of the coefficients. LiAlH4(s) + AlCl3(s) - AIHz(s) + LiCl(s) b. 11 Oc 12 d. 10

Answer 1

The complete step wise calculation is given as below:-

we have Ammo nium phog phite, (Nhy)3 PO3 since, molecul an wei ght c N 1y amu, P 31 amu H 1 amu hub 91 = Q Thun the Fonmula m ass afN4)3 PO3

tx)x3 +31 +16x3 amy 133 a (54t31+4 8 ) amy Fon mula mags 133 amu So) Cornect ophion willbe 133.09amu. Thun the

we have 27.9 779mu magg al X-28 28.976 qmu mass af X-23 amu 29.974 Mass af x-30 X-29+-2) -0 fx So,the atomic weight 3 27.977 +28.976 + 29.974) am 3 =28.97 amu. the cosune ct o ption willbe So1 28.97 amu.

given b Reaction LIARHY S)t ALcl3 (S) ALH3 (S) + LiCl s) given by Balanced neaction ARH3 S) +3LiCe AR Cl3 3Li AR Hu (S) t +3 ) = 11. Tot al coefficients =( 3 t 1 So the cornect ophion wil be 1.