51. In nuclear physics, what is a fission reaction that is maintained because neutrons released by the splitting of some nuclei themselves go on to split others, releasing even more neutrons?

 

52. When coal burns, the black shiny coal changes to grey ashes. The coal joins with the oxygen in the air to form gases, such as carbon dioxide. What is this process called in which substances combine or are broken down to form new substances?

 

53. Name the yellowish-green gas that has a strong, choking smell and is often added to water to kill germs?

 

54. Which synthetic chemical is odorless, non-toxic, non-flammable, and chemically inert? It is used in aerosol cans, refrigerators, and air conditioners, and for foam packing.

 

55. What is the cell or organism genetically identical to the cell or organism from which it has been derived called?

 

56. The cables used in the transmission of TV, telephone, and telegraph signals consist of two conductors, one within the other, separated by an insulator. What are these cables called?

 

57. Light is made up of many colors. Together these are known as a spectrum. What are the group of three primary colors?

 

58. If the red, green, and blue are mixed together equally, they look white. For paints and inks, the primary colors are red, green, blue, and magenta. What do they look like when mixed equally?

 

59. What term refers to a material that conducts heat or electricity?

 

60. Milk contains drops of fat suspended in water. What is the mixture called in which one substance is suspended in another?