Chalcopyrite, the principal ore of copper (Cu), contains 34.63% Cu by mass. How many grams of Cu can be obtained from 7.34x104kg of the ore? Enter your answer in scientific notation

Measurement and Matter Adding or subtracting and multiplying or dividing measurements 1/3 B A chemistry student must write down in her lab notebook the concentration of a solution of sodium hydroxide. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: The label on the graduated cylinder says: empty weight: 7.2 g . She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed 63.517 g. . She added water to the graduated cylinder and dissolved the sodium hydroxide completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 91.0 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. g-mL G

A chemist makes 460. mL of magnesium fluoride (MgF₂) working solution by adding distilled water to 170. mL of a 1.39 - stock solution of magnesium mmol L fluoride in water. Calculate the concentration of the chemist's working solution. Be sure your answer has the correct number of significant digits. 0×100 mmol L ?

Gaseous methane (CH4) will react with gaseous oxygen (O₂) to produce gaseous carbon dioxide (CO₂) and gaseous water (H₂O). Suppose 5.77 g of methane is mixed with 41. g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Be sure your answer has the correct number of significant digits. g x10 × Ś