67. Action of baking soda on sour milk

68. Chemical change

69. Quantity of baking soda to use with sour milk

70. Action of baking soda on molasses.

71. Quantity of baking soda to use with molasses.

72. Effect of cold water on a mixture of cream of tartar and baking soda.

73. Effect of hot water on a mixture of cream of tartar and baking soda.

74. Effect of hot water on baking powder.

75. Starch in baking powder.

76. Comparison of the time of action of different types of baking powders.