How many formula units are in 0.015 moles of PbBr2?

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.

What royal scientist used the 29th day of frozen vapor to encounter elements for mastering new culinary creations?

Achemist has dissolved a certain substance in water. the chemist knows that more of the substance could be dissolved into the water before it stops dissolving. therefore