18) A solution contains 30 ppm of some heavy metal and the density of the solution is 1.00g/mL This means that __ A) 100 g of the solution contains 30 g of heavy metal B) 100 gof the solution contains 30 mg of heavy metal C) the solution is 30% by mass of heavy metal D) there are 30 mg of the heavy metal in 1.0 L of this solution E) the molarity of the solution is 30 m Answer: D

To determine the correct answer, let's analyze the given information:<br /><br />1. The solution contains 30 ppm (parts per million) of some heavy metal.<br />2. The density of the solution is 1.00 g/mL.<br /><br />PPM stands for parts per million, which means that there are 30 parts of the heavy metal in 1,000,000 parts of the solution.<br /><br />To find the amount of heavy metal in 100 g of the solution, we can use the following calculation:<br /><br />30 ppm = 30 parts of heavy metal / 1,000,000 parts of solution<br /><br />To find the amount of heavy metal in 100 g of the solution, we can multiply the density of the solution (1.00 g/mL) by the volume of the solution (100 g / 1.00 g/mL = 100 mL).<br /><br />Since 1 mL of the solution contains 30 parts of the heavy metal, we can calculate the amount of heavy metal in 100 mL of the solution:<br /><br />30 parts of heavy metal / 1,000,000 parts of solution * 100 mL of solution = 3 mg of heavy metal<br /><br />Therefore, the correct answer is:<br /><br />B) 100 g of the solution contains 30 mg of heavy metal