What term is defined as weight of water divided by weight of hydrated gel x 100?

What term is defined as weight of water divided by weight of hydrated gel x 100?

• A. hydration factor
• B. oxygen permeability
• C. salt content
• D. water content

Answer: (D)

Water content is the percent of a hydrated hydrogel lens that is water by weight. It is defined as the weight of water in the lens divided by the total weight of the hydrated lens, times 100. This directly matches the formula in the question, making it the correct term. Oxygen permeability is a separate property (how easily oxygen passes through), not a weight fraction. Salt content refers to ionic content, and hydration factor isn’t the standard percentage by weight of water in the hydrated gel. For example, if a hydrated lens weighs 90 mg and its water content is 50%, the water portion weighs 45 mg. Higher water content generally increases oxygen transmission but can affect lens properties like strength and comfort.

Water content is the percent of a hydrated hydrogel lens that is water by weight. It is defined as the weight of water in the lens divided by the total weight of the hydrated lens, times 100. This directly matches the formula in the question, making it the correct term. Oxygen permeability is a separate property (how easily oxygen passes through), not a weight fraction. Salt content refers to ionic content, and hydration factor isn’t the standard percentage by weight of water in the hydrated gel. For example, if a hydrated lens weighs 90 mg and its water content is 50%, the water portion weighs 45 mg. Higher water content generally increases oxygen transmission but can affect lens properties like strength and comfort.