A study of the spectrum of the sun led to the discovery of helium.

True False

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

An object displaces 652 ml of water. the volume of the object is: 0.652 cm³ 6.52 cm³ 65.2 cm³ 652 cm³

What is the empirical formula of a compound that is 50.7% antimony and 49.3% selenium ?