Quimica

Solo disponible en BuenasTareas
  • Páginas : 3 (676 palabras )
  • Descarga(s) : 0
  • Publicado : 25 de diciembre de 2010
Leer documento completo
Vista previa del texto
Part one.
Write the name of the following compounds. 1 pt each answer
1. Fe2(CrO4)3 ______________________________ 4. Pb3(PO4)4___________________

2. Cr(SO4)3____________________ 5. P2O10 ____________________

3. Sn3P2 ________________________ 6. CaS ______________________

Part two.

1.The empirical formula of a compound is C3H8. If 2,00 mol of the compound has a mass of 264,48 g, what is the compound’s molecular formula? 4 pts

Molar Mass = 264.48 g = 132.24 g/mole 132.24 =3 x
2.00 mole 44.08

C9H24



2. Calculate the percent composition for each element of the compound lead (IV) phosphate. 5 pts

3. In a lighter there are 520, mg ofC4H10. Calculate the number of H atoms. 4 pts

4. Convert 3,560 x 1025 molecules of Copper ( II ) chloride to kg. 5 pts

5. A compound has 2,773 g Mg, 2,358 g P,and 4,869 g O, calculate the empirical formula. 5 points
What is the name of this compound ? 2 pts

A compound is 27,73% Mg, 23,58% P, and 48,69% O, calculate the empiricalformula.

27.73 g Mg x 1 mole = 1.141 moles = 1.5 x 2 = 3
24.3 g 0.7606 moles

23.58 g P x 1 mole = 0.7606 moles = 1 x 2 = 2
31.0 g 0.7606 moles

48.69 g O x 1 mole =3.043 moles = 4 x 2 = 8
16.0 g 0.7606 moles

Mg3P2O8 Mg3(PO4)2

6. What is the percent composition of each element in the formula CaCl2. 2H2O ? 5 pts

1 x 40.1 = 40.1g % Ca = 27.3 %

2 x 35.5 = 71.0 g % Cl = 48.3 %

4 x 1.01 g = 4.04 g % H = 2.75 %

2 x 16.0 = 32.0 g % O = 21.7 %

147.14

7. A compoundcontains C, H and O. A 5,90 g sample is burned to yield 11,18 g of CO2 and 3,66 g H2O. What is the empirical formula of the compound ? 6 pts

11.18 g CO2 x 1 mole x 1 mole C = 0.2541...
tracking img