What are some questions about weather

4Fe + 3O2  2Fe2O3 1. Classify the reaction that occurred between the iron and oxygen. 2. What evidence was there that a reaction took place?

Why are hydrogen molecules called elements but water molecules are called compounds?

A chemist carefully measures the amount of heat needed to raise the temperature of a 278.0g sample of C5H12S from 0.8degree celsius to 15.9 degree celsius. The experiment shows that 8.46X10^3J of heat are needed.

describes the sharing of a nonbonding electron pair on a nitrogen molecule with an oxygen atom, resulting in a nitrous oxide molecule?

Which factors cause a rising tide? A. The moon's gravity and Earth's rotation B. Density differences due to salinity and temperature C. Cold and warm ocean currents D. The ocean's conveyor belt and gyres

A vertical piston-cylinder device contains water and is being heated. During the heating process, 70 kJ of heat is transferred to the water, and heat losses from the side walls amount to 8 kJ.

Which of the following functions occurs in the part of the digestive system indicated by the arrow? Secretion of buffers and digestive enzymesAcid breakdown of swallowed foodsSecretion of bile and buffersAbsorption of water and ions

Sodium metal and water react to create sodium hydrogen and hydrogen gas through the unbalanced equation. Na + H20 - NaOH H2 By determining the limiting reactant, calculate the theoretical yield of hydrogen gas (in grams) if 79.

1) Mg (s) + 2 H + (aq) - --> Mg2 + (aq) + H2 (g)  H°12) Mg2 + (aq) + H2O (l) - --> MgO (s) + 2 H + (aq)  H°23) H2 (g) + 1/2 O2 (g) - --> H2O (l)  H°34) Mg (s) + 1/2 O2 (g) - --> MgO (s)  H°4

A substance has a solubility of 350 ppm. how many grams of the substance are present in 1.0l of a saturated solution