What are elements that bond with actinium

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

In the space, show a correct numerical setup for calculating the number of moles of co2 present in 11 grams of co2

How do you know when a chemical reaction has occurred