How many moles are in 0.423 g of Ca

Suppose a phosphorus atom forms a bond with a fluorine atom. What type of bond must between these two elements?

An unknown mineral scratches glass but will not scratch quartz. Which measure on the Mohs scale shows its hardness?

What is the mass of a rectangular cube with dimensions of 3 cm x 2 cm x to 10 cm and a density of 10 g/cm^3

Describe the movement of electrons by applying ground state and excited state when the electrons were energized?

A water sample consists of the following cadmium species and their percentages of the total cadmium concentration: Cd2 (36 %); CdHCO3 - (14 %); CdCl - (25 %); and Cd (OH) 2 (25 %). What percentage of Cd is toxic to aquatic organisms

How can a chemical reaction be slowed down?

The atomic number of an element is always the same as ___ A. The number of electrons B. The number of protons C. The number of neutrons D. The number of protons plus neutrons

Covalent bonds are formed when electrons are

Complete the chart. (Remember to enter a "0" if necessary.) Atomic Number: 3 1s: 2s: 2p: 3s: 3p: 4s: 3d: 4p: 5s:

How many water molecules are in 2.25 mol of water?