An isotope has a half life of 5 minutes. How much of a 100 gram sample of this isotope is left after 20 minutes?

Explain the relationship between forward and backward reactions in equilibrium, and predict how changing the amount of a reactant (creating a tension) will affect that relationship.

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space

What is the ph of a 0.0010 m hno3? 1.0 3.0 4.0 5.0