72.983 rounded to 2 significant figures

Which statement correctly describes part of the atomic model? a. atoms are made only of protons and electrons. b. the nucleus is made of protons and electrons. c. protons are outside the nucleus. d. electrons are outside the nucleus

Which of the following is a change in which a new substance is formed? A) cutting a slice of cheese into two pieces B) burning wood in a campfire C) an ice cube melting D) sanding wood into a pile of saw dust

A beach ball has a mass of 5 g and a volume of 20 cm3. What is the object's density?

During an effusion experiment, a certain number of moles of an unknown gas passed through a tiny hole in 50 seconds. Under the same conditions, the same number of moles of oxygen gas passed through the hole in 35 seconds.

The sum of the oxidation numbers in a neutral compound is always

How can you simulate the radioactive half-life of an element?

What are the horizontal rows on the periodic table?

What is 19 hundred thousandths in scientific notation

There state of matter that keeps its shape and volume when it is placed in a container

Our body solution tests at a pH of about 6.8. This pH is: