A white solid is heated and is observed to change to a liquid at 65 °C When the liquid is cooled, it becomes a white solid again at 65°C. Is the change chemical or Physical?

Which is a characteristic of mixtures? A. They are chemically bonded together. B. They can be classified as pure substances. C. They have fixed ratios between their components. D. They can be separated by physical processes.

Which is the balanced chemical equation representing the reaction between barium sulfide and platinum fluoride? BaS + PtF2 BaF2 + PtS A. BaS + PtF2 BaF2 + PtS B. BaS + 2PtF2 BaF2 + 2PtS C. 2BaS + PtF2 2BaF2 + PtS D. 2BaS + PtF2 2BaF2 + 2PtS

What will you change (the independent variable) in your test?

Static charges flow continuously true or false?

8. How many atoms of cobalt are in a 0.39 mole sample of CoC

Which term best describes the type of bonding in magnesium chloride

This equation indicates that the reaction gives off heat. What is this type of reaction called? 2C4H10 + ? O2? 8CO2 + 10H2O + heat a. an exothermic reaction b. an endothermic reaction c. absorption reaction d. precipitation reaction

Given the balanced equation representing a reaction: C3H8 (g) + 5O2 (g) = = >3CO2 (g) + 4H2O (g) What is the total number of moles of O2 (g) required for the complete combustion of 1.5 moles of C3H8 (g) ? (1) 0.30 mol (3) 4.5 mol (2) 1.5 mol (4) 7.

What increases in equal steps of one from left to right in the Periodic Table for the elements lithium to neon?

The organisms living together in a community are interdependent upon one another. Look at the food web below. In which of the following ways is a puffin dependent upon salmon? A. Puffins have a commensalistic relationship with salmon. B.