General Chemistry Answers

One of the first nuclear bombs based on the fission of U-235 had a maximum yield of 7.5 x10¹³ J.  If the fission of U-235 releases 1.8 × 10¹³ J/mol, approximately what mass of U-235 was used in this bomb?  (U-235 has a molar mass of 235.04 g/mol)

A concentrated solution of HCl has a molarity of 10.0 M. You add 23.50 mL to a flask and then dilute with water. The mass of the final solution is 125.0 g. What is the mass percent of HCl ?

39.0 mL of a pure, water-soluble liquid alcohol with a density of 1.854 g/mL is diluted with water, and the final mass of the solution is 5.00 × 10² g. What is the mass percent of the alcohol in this solution?

Find the mass percent if 6.86 g of KCl are dissolved to make a 250.0 g solution.

John has 2  marbles. Karen meets up with John on the way to Paul’s house. Karen has 5 marbles of her own. When they get to Paul’s house, he shows them his 9 marbles. What percentage of all of the marbles does John have? (Provide your answer to at least three digits.)

Find the number of moles of the H⁺ ion in 175 mL of 1.325 M sulfuric acid (H₂SO₄). Assume the acid fully dissociates.

The ionic compound, (NH₄)₂SO₄, will fully dissolve in water. If 15.16 g is dissolved in water to give a final volume of 402.0 mL, then find the following ion concentrations.

The concentration of the NH₄⁺ is:

The concentration of the SO₄^2- is:

Assume the given amount of RbF fully dissociates in water. Calculate the molarity of a solution if 138.42 g of RbF are dissolved into a solution of water that has a final volume of 2.00 L.

34.20 g of CaO is dissolved in 500.0 mL water. What is the concentration of the O^2- ion?

74.00 mL of a concentrated ethanol solution is added to a container to make 1.63 L of a 0.18 M diluted solution. What was the initial concentration of the ethanol?