Which of the follwing is a pure substance: sugar, salt, water, or pepper? Explain how you know.

after charcoal is added, the solution is filtered by hot gravity filtration. Why does the solution need to remain hot during the filtration to remove charcoal?

In the balmer series of the hydrogen atom, what is the smallest value of the principal quantum number of the initial state for e

John dalton proposed a theory that all matter is made up of individuals particles which cannot be divided. what were those particles?

The particles remain seperate and don't combine? What is this a mixture or a solution?

A compound used to test for the presence of ozone in the stratosphere contains 96.2% thallium and 3.77% oxygen. What is it's empirical formula? If it's molecular mass 456.76 g/mol, what is it's molecular formula

How much greater is the energy produced by a fusion reaction compared to a chemical reaction?

True or false. A bond between a metal atom and a nonmetal atom is likely an iconic bond

What is a precipitate? It is a liquid that forms from solution during a chemical reaction. It is a reactant that forms from solution during a chemical reaction. It is a solid that forms from solution during a chemical reaction.

The electron configuration for an atom is 1s22s22p2. How many electrons does the atom have? 4 2 6 5

When a piece of sodium carbonate reacts with dilute HCl, a gas X is produced. When gas X is passed through lime water then the solution turns milky and a white precipitate Y is formed a. Write the chemical formula of X, Y and (3) b.