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Take out paper and pen or pencil we need to review.

Take out paper and pen or pencil we need to review. Sit apart from each other. Try to do this with no talking while you’re figuring things out. A science student measured the mass of sand in a sample of crust to be 3.56 pounds of sand in a sample of 4.79 pounds.

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Take out paper and pen or pencil we need to review.

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  1. Take out paper and pen or pencilwe need to review. Sit apart from each other. Try to do this with no talking while you’re figuring things out.

  2. A science student measured the mass of sand in a sample of crust to be 3.56 pounds of sand in a sample of 4.79 pounds. What is the percent composition by mass of sand in this sample? (ROUND TO NEAREST WHOLE NUMBER) % COMP by MASS = Mass of the PartMass of the Whole X 100%

  3. A science student measured the mass of sand in a sample of crust to be 3.56 pounds of sand in a sample of 4.79 pounds. What is the percent composition by mass of sand in this sample? (ROUND TO NEAREST WHOLE NUMBER) % COMP by MASS = 3.56 pounds sand4.79 pounds crust X 100% 74% SAND

  4. A different science student measured the volume in a graduated cylinder to be 134.0 milliliters but it was actually 138.5 milliliters. 1st Question: when we do % Error, will our answer be a POSITIVE number or a NEGATIVE number? How can you tell? Write down this formula, figure out the percent error now. MV – AVAV X 100% % Error = Round to 3 digits please

  5. A different science student measured the volume in a graduated cylinder to be 134.0 milliliters but it was actually 138.5 milliliters. 1st Question: Here, % Error will be NEGATIVE, the measured value is UNDER the actual value. MV – AVAV X 100% % Error = 134.0 mL – 138.5 mL138.5 mL • X 100% % Error = = – 3.25% ERROR

  6. In a different sample of crust, scientists found that 1,325 pounds of crust contained 15.5 pounds of gold. What is the percent composition by mass of gold in this sample? Mass of the PartMass of the Whole • % COMP by MASS = X 100%

  7. In a different sample of crust, scientists found that 1,325 pounds of crust contained 15.5 pounds of gold. What is the percent composition by mass of gold in this sample? 15.5 pounds gold1,325 pounds crust • % COMP by MASS = X 100% = 1.17% is gold

  8. What do these element symbols stand for? Zn Al Cl He Na Ag Ne Fe Ni Pu

  9. What do these element symbols stand for? Zn zinc Al Aluminium Cl chlorine He Helium Na sodium Ag Silver Ne neon Fe Iron Ni nickel Pu Plutonium

  10. What are these compound symbols? CO2 CH4 C8H18 NaCl CaCl2 PCl3

  11. What are these compound symbols? CO2 carbon dioxide CH4 methane, Bunsen Burner Gas C8H18 octane, car go juice NaCl sodium chloride (table salt) CaCl2 ice melt, calcium chloride PCl3 phosphorous tri chloride

  12. Tomorrow’s quiz is on: Error, percent error, percent composition by mass, and some chemical symbols I will provide you with the formulas, you are not supposed to memorize them. You are supposed to memorize HOW to use them.

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