Concentrated hydrochloric acid has a density of 1.19 g/ml. What is the mass of 250.0 mL of HCl(aq)?

Dwayne filled a small balloon with air at 298.5 k. he put the balloon into a bucket of water, and the water level in the bucket increased by 0.54 liter. if dwayne puts the balloon into a bucket of ice water at 273.15 k and waits for the air inside the balloon come to the same temperature, what will the volume of the balloon be? assume the pressure inside the balloon doesn’t change. type the correct answer in the box. express your answer to the correct number of significant figures. the volume of the balloon at 273.15 k is liters.

A+b→2c when the reaction begins, the researcher records that the rate of reaction is such that 1 mole of a is consumed per minute. after making changes to the reaction, the researcher notes that 2 moles of a are consumed per minute. what change could the researcher have made to effect this change?

Explanation for basic character?