What causes a nucleus to become radioactive?

A sample of a material has 200 radioactive particles in it today. Your grandfather measured 400 radioactive particles in it 90 years ago.

An apple pie needs 10 large apples 2 crusts (top and bottom) and 1 tablespoon of cinnamon. Write a balanced equation that fits this situation. How many apples are needed to make 25 pies?

Which element has an atomic number 10 and an atomic mass of 20

A 40g sample of polyisoprene, which has a specific heat capacity of f 1.88 J 1.°c, is dropped into an insulated container containing 100g of water at 55C and a constant pressure of 1 atm. The initial temperature of the polyisoprene is 1.5C.

Rudri studies for her physical science test on the history of the atomic model. She creates a table to show how the atomic model has changed over time.

When 1 g of sodium chloride (NaCl) is placed in 100 g of water, a solution results. Once the solution is prepared, water is now considered what part of the solution?

1. How is pressure affected as depth increases? 2. As the sun heats the surface of the oceans, two layers of water result. What separates the layers? 3. How is temperature affected when? (a) the depth increases (b) the latitude increases 4.

Are nails in a jar with water a chemical change

What is the molarity of a solution composed of 4.73 g of potassium iodide (KI) dissolved in enough water to make 0.169 L of solution? Answer in units of M.

Suppose you were given a substance and asked to determine whether or not it was a plasma. Write the characteristics you would look for to identify the substance.