How is a pure substance different from a mixture?

A

Pure substances cannot be separated by physical means

B

Mixtures cannot be separated

C

A pure substance is heterogeneous

D

A mixture is made of one substance

What are the concentrations of hydrogen ion and hydroxide ion in household ammonia, an aqueous solution of nh3 that has a ph of 11.50?

4.65 L of nitrogen at standard pressure is compressed into a 0.480 L container. What is the new pressure in kPa?

What happens to the half-life and mass of reactants broken down during a nuclear decay reaction? The half-life of the reactants in a nuclear decay reaction remains constant over time, and the mass of the reactants that are consumed stays the same.

How many feet are contained in. 399 km

True or False? A change in color is evidence of a chemical reaction

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What is the net ionic equation for the precipitation reaction between bacl2 and na2so4? a bacl2 (aq + na2so4 (aq? baso4 (s + 2nacl (aq b ba2 + (aq + so42 - (aq? baso4 (s c na + (aq + cl - (aq?

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Why does the burning of magnesium ribbon start the reaction between iron oxide and aluminium when making iron?