Problemas

1) A sample of calcium carbonate (CaCO_(3)) has a mass of 100.0 grams, how many formula units of CaCO_(3) are there? SHOW WORK FOR CREDIT BOX IN ANSWER 2) How many grams is 8.0times 10^15 molecules of table sugar (C_(12)H_(22)O_(11)) SHOW WORK FOR CREDIT, BOX IN ANSWER
Solución

Víctormaestro · Tutor durante 5 años

4.6 (317 votos)
Responder
1) To find the number of formula units of calcium carbonate (CaCO3) in a 100.0 gram sample, we need to follow these steps:<br /><br />Step 1: Calculate the molar mass of CaCO3.<br />The molar mass of CaCO3 is the sum of the molar masses of calcium (Ca), carbon (C), and oxygen (O).<br />Molar mass of Ca = 40.08 g/mol<br />Molar mass of C = 12.01 g/mol<br />Molar mass of O = 16.00 g/mol<br />Molar mass of CaCO3 = 40.08 g/mol + 12.01 g/mol + (3 * 16.00 g/mol) = 100.09 g/mol<br /><br />Step 2: Convert the mass of the sample to moles.<br />Mass of CaCO3 = 100.0 grams<br />Moles of CaCO3 = Mass / Molar mass<br />Moles of CaCO3 = 100.0 g / 100.09 g/mol = 0.9995 moles<br /><br />Step 3: Convert moles to formula units.<br />1 mole of CaCO3 contains Avogadro's number of formula units, which is 6.022 x 10^23 formula units.<br />Number of formula units = Moles * Avogadro's number<br />Number of formula units = 0.9995 moles * (6.022 x 10^23 formula units/mole) = 5.99 x 10^23 formula units<br /><br />Therefore, there are approximately 5.99 x 10^23 formula units of CaCO3 in a 100.0 gram sample.<br /><br />2) To find the mass of 8.0 x 10^15 molecules of table sugar (C12H22O11), we need to follow these steps:<br /><br />Step 1: Calculate the molar mass of C12H22O11.<br />The molar mass of C12H22O11 is the sum of the molar masses of carbon (C), hydrogen (H), and oxygen (O).<br />Molar mass of C = 12.01 g/mol<br />Molar mass of H = 1.01 g/mol<br />Molar mass of O = 16.00 g/mol<br />Molar mass of C12H22O11 = (12 * 12.01 g/mol) + (22 * 1.01 g/mol) + (11 * 16.00 g/mol) = 342.30 g/mol<br /><br />Step 2: Convert molecules to moles.<br />1 mole of C12H22O11 contains Avogadro's number of molecules, which is 6.022 x 10^23 molecules.<br />Moles of C12H22O11 = Number of molecules / Avogadro's number<br />Moles of C12H22O11 = (8.0 x 10^15 molecules) / (6.022 x 10^23 molecules/mole) = 1.33 x 10^-8 moles<br /><br />Step 3: Convert moles to grams.<br />Mass of C12H22O11 = Moles * Molar mass<br />Mass of C12H22O11 = 1.33 x 10^-8 moles * 342.30 g/mol = 4.56 x 10^-6 grams<br /><br />Therefore, 8.0 x 10^15 molecules of table sugar (C12H22O11) is equivalent to 4.56 x 10^-6 grams.
Haz clic para calificar: