How many grams of oxygen are in 4.50 x 1025 molecules of potassium sulfate?

What three things determine the shape and size of a puddle when water is poured out onto a surface

Imagine that twenty i. u.’s of enzyme z were catalyzing the above reaction for one minute, under vmaxconditions, in a 3.00 ml assay volume. the assay is buffered with 20 mm phosphate buffer, ph 7.60. what will the ph be at the end of that one minute?

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.