How would one know if something is an element?

What are the two parts of an atom?

What is the [h+] if the ph of a solution is 1.65? [H+] = [?] x 10^? answer [?] EDIT: The answer is [h+] = 2.24 x 10^-2

The table below shows the electronegativity values of various elements on the periodic table. electronegativities which pair of atoms would form a covalent bond?

What is the maximum mass of s8 that can be produced by combining 87.0 g of each reactant? 8so2+16h2s=3s8+16h20?

Why different fuels are used in different vehicles?

If the heat released during condensation goes only to warming the iron block, what is the final temperature (in ∘C∘C) of the iron block? (Assume a constant enthalpy of vaporization for water of 44.0 kJ/molkJ/mol.)

Which of the following is not a disaccharide? A) sucrose B) maltose C) lactose D) amylose E) all of the above are disaccarides

The process by which a semipermeable membrane allows water molecules, small molecules, and ions to pass through while retaining large particles

Ice melting, water boiling, lighting a match, grape juice freezing. Which statement describes evidence of a chemical reaction

An ion from a given element has 22 protons and 18 electrons. what is the charge on the ion?