How many kilograms of urea (60.01 g/mol) are required to prepare 6.7 L of solution at 8 M (3 significant digits)?

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Give a real-world example of an energy transformation that uses two of the following forms of energy: chemical, mechanical, nuclear, gravitational, radiant, electrical, thermal (heat), and/or sound.

Asap at one point in history people could measure temperature by looking at the volume of a sample of gas. suppose a sample in a gas thermometer has a volume of 135ml at 11.0°c. indicate what temperature would correspond to each of the following volumes: 113 ml, and 155 ml.