Calculate the relative formula mass of calcium carbonate, CaCO3. (relative atomic masses: C = 12, O = 16, Ca = 40)

An atom of element X has an atomic number of 119 and a mass number of 319. How many electrons does it have?

Name of this structure?

What is the electron configuration of nitrogen (atomic #7)

the horizontal lines on the periodic table are called

What is an advantage of having internationally agreed hazard symbols?

Is chlorine an alkali metal, alkaline Earth metal, halogen or noble gas?

Rauda wants to separate 2 liquids. Liquid A has a boiling point of 65C and liquid B has a boiling poit of 95C. She sets up a fractional distillation. Which liquid is collected first?

Throughout the experiment the volume of hydrogen and the volume of oxygen are measured at two-minute intervals. Describe what the results show about the volumes of hydrogen and of oxygen produced in this experiment.

An atom of element X has an atomic number of 119 and a mass number of 319. How many neutrons does it have?

Definition of catalyst: a substance that speeds up a reaction without altering the ________(a) and is unchanged _______(b)

Place the following pH values in order of increasing acidity: 4,1,7, 12, 6