Heterogeneous materials are always mixtures. Are homogeneous materials always pure substances? Explain.

Robin and Alex are discussing how water molecules form when hydrogen and oxygen atoms combine. Robin writes the following chemical equation to explain the formation of water.

Which is a common characthist of both science and pseudoscience

Which process does not involve a chemical change? 1. cleaning the shower with lime away 2. burning charcoal on the grill 3. boiling water 4. digesting food?

What is the density of iridium metal? (Ir: 192.2 g/mol; face-centered cubic with 3.83x10^-8 cm edges).

The molecular mass of methyl ethanoate is 75.1 amu. calculate the molecular mass of propanoic acid, an isomer of methyl ethanoate. express your answer with the appropriate units.

When an aqueous solution of silver nitrate is mixed with an aqueous solution of potassium chloride which are the spectator ions?

Investigating changes in colligative properties involves the measurement of a solution's concentration in molality instead of molarity because

Consider the following representation of a reaction mechanism. Step 1: Unimolecular (fast) Step 2: Bimolecular (slow) Step 3: Unimolecular (fast) Which conclusion about the rate law for the reaction above is reasonable? A.

1. Which of the following best describes an example of pure chemistry? a) testing the effects of lower concentrations of a drug on humans b) studying chemicals containing carbon c) developing a cure for osteoporosis d) finding an antidote for a new

Problem 1: For which of the following activities might you want to hire a chemist? A. building a garage B. testing a sample of water from a well C. finding a comet D.