A. Berapakah jumlah mol yang terdapat pada 0.4 gram kalsium (Ar Ca = 40 ). B. Berapakah jumlah atom oksigen dalam 11 gram karbon dioksida (Ar C-12; O = 16 ).... C. Jika pada keadaan STP berapakah volume 1 gram gas hidrogen(H)..... D. Volume hidrogen yang bergabung dengan 24 liter oksigen untuk menghasilkan air adalah.

<p>A. mol = gram : Mr</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 0,4 : 40&nbsp;</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 0,01 mol</p><p>B. untuk menghitung jumlah atom O2 kita cari mol CO2 nya dulu</p><p>&nbsp; &nbsp; &nbsp; mol CO2 = gram : Mr</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 11 : 44</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 0,25 mol</p><p>&nbsp; &nbsp; Jumlah partikel CO2 = mol x L (tetapan avogadro)</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 0,25 x 6,02 x 10^23</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1,505 x 10^23</p><p>Karena setiap &nbsp;molekul CO2 mengandung 2 atom oksigen sehingga</p><p>Jumlah partikel O2 = 2 x 1,505 x 10^23</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 3,01 x 10^23 atom</p><p>C. untuk menghtiung V STP cari molnya dulu</p><p>&nbsp; &nbsp; &nbsp;mol = gram : Mr</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 1 : 1&nbsp;</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1 mol</p><p>&nbsp; &nbsp;Volume = mol x STP</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1 x 22,4</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 22,4 L</p><p>&nbsp;</p><p>D. Persamaan reaksi</p><p>&nbsp; &nbsp;2H2 + O2 -&gt; 2H2O (setara)</p><p>&nbsp; &nbsp;dalam hukum gai lussac berlaku perbandingan V sama dengan &nbsp; &nbsp; &nbsp; &nbsp;Perbandingan koefisiennya</p><p>V &nbsp;hidrogen = 2 : 1 x 24 L</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 48 L</p><p>&nbsp;</p>