A sample of pure copper has a volume of 3.75 cm3.
Calculate its mass. ​

Acylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon and 5.00 moles of helium. if the gas mixture is at stp, what is the partial pressure of the argon

Describe at least two advantages and two disadvantages of using hydropower as a source of energy.

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted