What are the indications/signs that a chemical change has occurred?

What Element is found in column 16, period 2?

A mixture of 5 gases exerts a pressure of 101.8 kPa. The pressure exerted by hydrogen gas is 40.8 kPa, by bromine gas is 26.7 kPa, by Fluorine gas is 3.5 kPa, and by helium gas is 12.7 kPa. What is the pressure exerted by the final gas?

1. Is O2 a compound? Explain. 2. Is O2 a molecule? Explain. 3. State the law of conservation of matter, and give an example demonstrating its meaning. 4. Electrolysis is used to break liquid water into hydrogen and oxygen gas.

Which of these substances contributes to soaps slippery texture? - an acid - a base - carbonate - water

The electrolysis of molten NaCl is an industrial process. What does the electrolysis produce? A. Na and Cl2 B. H2 and O2 C. Na + and Cl- D. NaOH and Cl2 I think it's A not sure

The charge of the stable ion of P

A change in the properties of matter where chemical bonds are broken and new bonds are formed is a.) a chemical change b.) a physical change c.) an ionic change d.) a covalent change

Write a chemical equation for the chemical reaction in which calcium carbonate (CaCO3) produces calcium oxide (Cao) and carbon dioxide (CO2).

How do you know the difference between a compound and mixture?

A 68.4-g sample of potassium chloride was added to 200.0g of water at 20 degrees C. Is the solution saturated, unsaturated, or supersaturated?