Question

I was wondering if someone could help me with some problems on my test, my teacher allows me to correct them then give them back for 1/2 credit. Along with the correct answer for each I'd like to know why the answers are wrong and why the new answer is correct. The questions with a red mark are the incorrect ones.

test a de that contains 0.890 g of sulfur. 7. Calculate the mass of silver in a. 1.08 g 1.788 c. 3.00 g d. 5.99 g e. 6.89 8. Calculate the formula mass of magnesium phosphate. 119.28 u b. 143.59 u c. 214.25 d. 262.87 e. 333.53 u 9 Calculate the molar mass of molecular iodine. @126.9 g/mol b. 253.8 g/mol c. 79.9 g/mol d. 159.8 g/mol e. Only atomic masses, and not molar masses can be calculated for elements 10. Barium peroxide, Baos, breaks down into barium oxide and oxygen. Write the balanced chemical equation for this reaction. What is the coefficient for barium oxide? a. 3 b. 1 c. 5 @4 11. When sodium chloride and silver nitrate solutions are combined, the reaction shown below occurs. Write the balanced chemical equation for this reaction. What is the coefficient for silver nitrate? a. S b. 4 c. 3 d. 2

Answer 1

thank you very much .hope this will help you.good luck
Ag =107.0 7 s = 32 DATETITIO Agas Molar Mass of A925 = 2x107.0+32 = 215.6 +32 = 249.6 Step-1 32 gram Sulfur contain Sample of Ages have = 215.6g Ag are - 215.6 1 gram Sulfer Contain sample of Ages have a Ag Now 0.890 gram Sulfrer Contain sample of Ag2 have = 215.6 x 0.890 gram Ag 2 Ans d = 5.gg grom Ag And (0) formula of Magnesium phosphate 32 32 2 X 134 = Mgz (PO4)2 Alemic mass mg = 24.305 g P = 30.97 0 = 15.999 Man (204)2 = 3 X 24:305+2x30:97+BX15.999 = = And d 72.915 + 61.94 + 127.992 262.0 u. PAGE

DATE DUTII 19 Molar Mass of I = 126.9 Iz (molecular lodine) I2 = 2x 126 9 = 253.8 g/mol Ans - br 10 Be Oz - (Bao+ ko? in faction) Balanced 2 Bao2 - Bao) + O2 (whole Number) Coefficient of Barium oxide = 2 Ans (eg in Balmced Equation we have 2mefe Зи 0 До у 1, 2