Sand is converted to pure silicon in a three step process. the third step is sicl4(g) + 2mg(s) → 2mgcl2(s) + si(s) δh = –625.6 kj what is the enthalpy change when 25.0 mol of silicon tetrachloride is converted to elemental silicon? multiple choice –7820 kj –25.0 kj –3.13 × 104 kj none of these choices are correct. –1.56 × 104 kj

Gusing the milligrams of ascorbic acid you entered above, the ratio of total sample volume to aliquot volume, and the total milligrams of the vitamin c tablet that you dissolved, calculate the mass of ascorbic acid in the vitamin c tablet for each trial. do this by scaling up to find the amount (mg) of ascorbic acid in your 250 ml flask. enter your calculated mass of ascorbic acid in the vitamin c tablet, for each trial. be sure to enter your calculated mass in the corresponding order that you entered your milligrams of ascorbic acid. the milligrams of ascorbic acid you entered for entry #1 previously should correspond to the mass of ascorbic acid that you enter for entry #1 here.