An isotope of cesium (cesium-139) has a half-life of 31.5 years. If 1500 g of cesium-139 disintegrates over a period of 189 years, how many grams of cesium-139 would remain?

How much energy is made when a pice of wood burns. how do you know

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.

What is one real world example of a colligative property?