Accurate measurement by ounces makes a critical contribution to many processes. Ounce measurements assure correct results in cooking and baking, in various trades that involve selling products, in science, and in jewelry making and other arts. Learn the measurement standards and the techniques for measuring to obtain correct a correct 20-ounce measurement the first time and every time.

Liquid Measurements

Measuring cups designed for cooking and baking often come in clear glass with marks on them indicating the measurement in both fractions of a cup and in liquid ounces. Common measuring cup sizes include 1-cup, 2-cup and 4-cup. Buy one from a retailer that sells cookware. Science labs use measuring cups for liquids as well. One liquid cup equals 8 ounces. A 1/2-cup equals 4 ounces and a 1/4 cup equals 2 ounces and an 1/8 cup equals 1 ounce. To obtain 20 ounces, measure out 2 1/2 cups: 2 cups equals 16 ounces plus 1/2 cup equals 4 ounces to add up to a 20 ounce measurement.

Technique

Obtain a clear measuring cup that holds 4 cups. You can also use a 1-cup or 2-cup measuring cup if that's what you have on hand. The 4-cup measuring cup allows for measuring 20 ounces in one step. The 4-cup measuring cup holds 32 liquid ounces. Place the cup on a table or counter. To measure 20 ounces, find the mark for 2 1/2 cups. Slowly pour what you wish to measure into the 4-cup measuring cup. Watch the mark at 2 1/2 cups and stop pouring when the substance reaches that level. With a 1-cup measuring cup, fill it to the 8-ounce mark twice, then fill it to the 4-ounce mark. With a 2-cup measuring cup, fill it to the 16-ounce mark once, then fill it to the 4-ounce mark.

Dry Weight

The measuring cup's ounces refers to liquid. It works to measure water, oil, chemical solutions or any other liquid for example for a recipe, diet tracking or a formula for science class. It's also used to measure dry products for cooking such as oatmeal or beans. Dry cup measurements refer to volume: one cup in size, rather than 8 ounces. Dry product ounces require weighing. A 1/2-cup of tomato chunks weighs more than 1/2 cup of coconut flakes. A 1/2 cup of river rocks weighs more than a 1/2 cup of sawdust. To measure dry weight, for example, to check the amount of a chunk of baking chocolate or to determine 5 ounces of sand for a science or art project, use a scale designed to measure weight, such as a food scale, postal scale, or jeweler's scale. The Alabama State Department of Education advises that a liquid measurement is written "fluid ounce" or "fl. oz." "Ounce" or "oz." without the fluid qualifier refers to weight.

Source:

University of Houston: Units of Capacity: How to Read a Measuring Cup

Alabama State Department of Education: Weighing and Measuring