Which equation obeys the law of conservation of mass?

2Fe + 3O2 → 2Fe2O3

4Fe + O2 → 2Fe2O3

Fe + O2 → Fe2O2

4Fe + 3O2 → 2Fe2O3

What does the position of lithium on the periodic table tell you about its tendency to react with other elements?

When two substances are mixed together, a color change is observed. Does this mean that a chemical reaction has definitely occurred? - Yes because any change indicates a chemical reaction. - No because some physical changes produce color changes.

Consider the reaction cacn2 + 3 h2o → caco3 + 2 nh3. how much nh3 is produced if 187 g of caco3 are produced? 1. 2.13 mol 2. 63.6 mol 3. 3.74 mol 4. 36.1 mol 5. 1.06 mol 6. 72.3 mol

What do we call the part of the microscope where we put the slide? A. the light B. the eyepiece C. the stage D. the base

Cal the molarity of solution prepared by dissolving 250 of Ca (NO3) 2 to make 2.5L of solution

How are the number of protons and the number of neutrons related?

If a sample of copper with a density of 8.90 g/cm3 displaces 13.0 mL of water when placed in a beaker, what is its mass? a 1.46 g b. 0.685 g c. 116 g

Which statement accurately describes the origin and expansion of the universe

Conversion. 5 km to inches

How many kilojouls are required at 0c to melt an ice cube with a mass of 25g