How Much Does A Square Foot Of Water Weigh

Close view of a chef measuring the weight of a glass of water in the kitchen

The weight of water can change based on factors similar temperature or added salt.

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Our lives revolve around water — for hydration, recreation and then much more. And agreement how factors similar temperature, state and density touch on the weight of water tin help you when it comes to cooking.

What Is the Weight of H2o?

Scientists use two measurement systems to ascertain the weight of h2o. In the metric system, which is more widely used around the world and in cooking, the unit of measurement weight of water is approximately 1 gram per cubic centimeter at 25 degrees Celsius, according to the National Library of Medicine. In regal measurements, information technology'due south nigh 62.4 pounds per cubic foot at 77 degrees Fahrenheit.

Merely the weight of water is best understood when yous remember near it in terms of mutual quantities:

A cup of water weighs about 224 grams (one-half a pound), per the National Institute of Standards and Technology.
A liter of water weighs about 1 kilogram (2.2 pounds), according to the U.s. Geological Survey (USGS).
A gallon of water weighs well-nigh 3.79 kilograms (8.35 pounds), per the USGS.

Variations in the Weight of H2o

The weight of h2o is approximate, however, because it can vary based on factors like temperature and force per unit area, co-ordinate to the USGS. It tin also fluctuate if there are substances in the water, like table salt.

Why It Matters

Water weight is important when it comes to cooking. Many recipes are based on the weight of ingredients, rather than fixed amounts like tablespoons or cups. And so if you're lacking a nutrient scale, understanding roughly how much certain quantities of water weigh can assist you lot ace any meal.

H2o Density

The density of any substance will change as factors like temperature and pressure brand the material aggrandize and contract, and water is no exception, according to the USGS.

Density is a measure of how much mass a substance has, per the U.S. Nuclear Regulatory Commission (NRC). A pocket-size volume of a very dense material like lead will exist heavy, whereas a large book of a depression-density material like Styrofoam weighs much less.

Density is ordinarily stated in units of mass per book; for instance, grams per cubic centimeter. On Earth, this means that the density of water at room temperature is the aforementioned every bit the weights listed above, per the USGS.

Weight vs. Mass

Most people don't make a stardom betwixt mass and weight, but to a scientist, these are ii different measurements. Mass is the bodily concrete bulk of a substance, co-ordinate to the NRC. Weight is the forcefulness with which gravity pulls on that mass.

For instance, a cat has more than mass than a mouse. But a cat on the moon might counterbalance less than a mouse on Earth due to unlike gravitational pulls. But because you're likely only dealing with water on Earth, the weight of h2o won't fluctuate based on gravity.

How Water Density Varies

The weight and density of h2o can fluctuate based on its state, nevertheless. In addition to liquid, h2o can be a solid (water ice) or gas (vapor), per the USGS. The density of ice, gas and liquid are different, which consequently changes water's weight from grade to form.

Ever wonder why ice floats? That's because ice is less dumbo than water. When h2o freezes at 32 degrees F (0 degrees C), its molecules spread out to class a more rigid structure, according to the USGS.

Vapor, on the other manus, occurs when liquid water hits 212 degrees F (100 degrees C) and the molecules movement around rapidly and evaporate, according to the USGS. Consequently, gas is less dense than the other states of h2o.

Then there'southward salt h2o to consider. Salt h2o is more dense — and thus weighs more — than fresh h2o due to the added mass of salt, according to the USGS.