In a chromatography experiment, chlorophyll pigments are separated using paper. What is the stationary phase in this experiment?

A) water

B) chlorophyll pigments

C) paper

D) gas

Determine the oxidation number of the element that is underlined within the compound. BaCrO4 (Cr is underlined) Answer choices: +2 +4 +6 -4 -2 -6

Susan shakes a bottle of oil and vinegar salad dressing, then sets it on the table. After a while, the oil rises to the top and the vinegar settles on the bottom of the bottle. Why does this happen?

At a constant temperature, a sample of a gas in a balloon that originally had a volume of 2.2 l and pressure of 749 torr has a change of pressure to 629 torr. calculate the new volume in liters.

We can also use the equation for enthalpy change for physical phase changes. Consider the phase change H2O (l) → H2O (g). Calculate ΔHrxn.

When explaining chemical reactions to a friend, Brianna models a reaction by taking several colors of modeling clay and making a sculpture of a horse. Which type of chemical reaction is Brianna most likely explaining?

Where did the longest tsunami form?

Calculate the number of H atoms in 0.190 mole C 6 H 14 O .

What fuel is produced by the electrolysis of water? chlorine gas hydrogen gas natural gas oxygen gas

Model describe how you would show j. j. thomson's model of the atom using small beads and clay

Switching one substance for another is called ... ? a) displacement b) synthesis c) decomposition d) oxidation