Question

How many grams of Si are there in a sample of Si that contains 3.53x1023 atoms? | grams

Answer 1

day (1) moles of Si= atom - 3.53X10 atom NA - 6.022x10? atm/mal. = 0.586 mol mass of si= moles X Malar mass - 0.586 md x 28.08 g/mol = 16.469 2) moles of NFZ = mass = 3.23g malar mass 71 g/mol = 0.0455 mol molecules of NWE - males x 6.022X10% molecull = 0.0455X6.022 X1023 - 0.244X1023 moleculs. I molecule of NF₃ = Inote atom of N so atom of N= 0.27481023 atom = 0 • 27X1023 atom 2 2.7 X1022 atom

moles of NFZ = et molecules 71 = 1028X1022 6.0 22X1023 23 = 0.0213 mol Madd of NF3 = males X molan maus - 000213 mol x 71 g/mol = 1051g mass of fluguine in 19 NFZ = 3 X Mass of fluorine atom . Molore mass of NF3 = 34 19 = 0.803g l seu mats of fluorine in 115190f Nf3= 1.51X0.803 = 1021g aus 8 9 I molecule of Mg Conly has latam of Mg. so. Let we have imale of Mg(OH)₂ 80, mass of Mycon), = males x molaumas - 1x 58.329= 58.329 mass of my in Imale My con la = 1x Malaumans of my E 1 X 24.3 = 24.39 So mass %= mass of Mg x 100 mass of Mg(OH)2 = 24.39 x 100 = 41067% 58.32g Thank you, May ist help ypper