Archimedes, a famous Greek scientist, was given a problem by King Hieron II of Syracuse (Sicily). The king suspected that his crown, which was supposed to be made of pure gold, contained some silver alloy, and he asked Archimedes to prove or disprove his suspicion. (It turned out that the crown did not contain silver.) How would you experimentally determined whether or not the crown was pure gold?

You have a mole of ping pong balls and want to ship them to a near-by town. You have packing boxes that measure 24 inches by 24 inches by 18 inches. How many boxes do you need to pack up all the ping pong balls? The radius of a ping pong ball is 20 mm. If you make any approximations or assumptions, please list them.

If 0.42 mg calcium fluoride, CaF2 is used as above to add fuoride to the drinking water, doesCaFz add more fluoride than 0.42 g of NaF in the 250 mL glass of water? Justify your answer.

Suppose the absorbance of a 0.084 M solution of nickel(II) nitrate in water is measured to be 0.305 in a cuvette with a path length of 1.00 cm. If the solution is then diluted by a factor of 3, what do you expect the absorbance of the diluted solution to be, when measured in the same 1.00-cm cuvette? Round your answer to the correct number of significant figures

You have 2 beakers, one contains a salt solution and the other sugar solution. What particles are found in each solution? Which solution will conduct electric current? Explain your choice.

4 The mixture used in today's experiment was prepared as a 1:1:1 mixture (by mass) of sand, salt, and salicylic acid. Do your results for the mass of each recovered solid indicate a 1:1:1 composition of the mixture? Explain your response.

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: 8.200 g • She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed 45.74 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 24.09 ml. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. ml

Nitroglycerine is a shock-sensitive compound that decomposes as follows:  2 C3H5N3O9(l)     -->     6 CO2(g)   +  3  N2(g)   +   ½ O2(g)   +   5 H2O(g) 10.0 kg of nitroglycerine sits in a 5.0-L cylinder.  A chemist, angry that an experiment didn’t work, foolishly kicks the cylinder, thereby inadvertently performing his last and most dramatic experiment.  The final temperature of the product mixture is 595 oC.  Assume ideal gas behavior and complete decomposition.  Calculate the total pressure (atm) in the cylinder the moment before the explosion.

4/3 pie * (0.0576/2)^3=0.00010061=1.00=1.00x2.20/60.02=0.036654449*60.09=2.202565811=2.2E-18 ? is this even right? i've been struggling with this problem for hours.

A chemist prepares a solution of iron (II) chloride (FeCl₂) by measuring out 1.0 g of FeCl₂ into a 250. mL volumetric flask and filling to the mark with distilled water. Calculate the molarity of Canions in the chemist's solution. Be sure your answer is rounded to 2 significant digits. 7 mol L 0x x10 X Ś