How to balance chemical formulas

John weighs 115 kg. Sally weighs 115 lb. Who is heavier of the two?

A scientist is studying a chemical reaction. She predicts that after the reaction the product will have less chemical potential energy than the reactants had originally

Is it likely that an atom of Te would substitute for an atom of O in a solid compound? yes no indeterminate

Which variable can affect your grade on a spelling test? A) how much you studied B) what you are wearing C) the weather D) the day of the test

Which is the electron configuration for lithium?

The molar mass of water (H2O) is 18.02 g/mol. Yun needs 0.025 mol H2O for a laboratory experiment. She calculates that she needs 72.0 g H2O for the experiment. Yun's calculation was incorrect because she set up her unit conversion incorrectly.

I'm doing isotope homework and I need the find the number of protons, neutrons, and electrons first one is chromium-58 and chromium-63

Trisha and her lab partner were conducting a variety of experiments to produce gases: hydrogen, oxygen, and carbon dioxide. In one experiment, they added a piece of magnesium ribbon to 10 milliliters of hydrochloric acid.

what mass of magnesium is required to react with excess nitrogen to produce 0.500 mol magnesium nitrade

Silver chromate is sparingly soluble in aqueous solutions. the ksp of ag2cro4 is 1.12 * 10-12 m3. what is the solubility (in mol/l) of silver chromate