molecular weight

American  

noun

Chemistry.

1. the average weight of a molecule of an element or compound measured in units once based on the weight of one hydrogen atom taken as the standard or on 1/16 (0.0625) the weight of an oxygen atom, but after 1961 based on 1/12 (0.083) the weight of the carbon-12 atom; the sum of the atomic weights of all the atoms in a molecule. mol. wt.

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molecular weight British  

noun

1. the former name for relative molecular mass

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molecular weight Scientific  

1. The sum of the atomic weights of the atoms contained in a molecule.

2. Also called relative molecular mass

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molecular weight Cultural  

1. The sum of the atomic weights of all the atoms in a molecule.

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Etymology

Origin of molecular weight

First recorded in 1875–80

Example Sentences

"To date, it is not well understood how nitrogen molecular ions with large molecular weight can exist at such high altitudes," he continued.

From Science Daily

"It's a very stable chemical with a low molecular weight," Fairey said.

From Science Daily

Since the molecular weight of salt is very small, we use a special membrane that filters it through very small holes that allows only these molecules to pass through.

From Salon

In this study, the researchers synthesized PSPBs with different molecular weights and added varying amounts of hydrophobic monomers individually and with different alkyl chains through a process known as reversible addition-fragmentation chain transfer polymerization.

From Science Daily

"The traditional chemical processes that use a lot of acid and base to process and extract chitin usually produce chitin with small molecular weight that may have limited applications," Luo says.

From Science Daily