Nitrogen is made up of two isotopes N-14 and N15. given nitrogen's atomic weight of 14.007 what is the percent abundance of each isotope

Which of the following provides evidence that a chemical change has taken place?

Most reactions between an acid and a base form a salt and water. Which term describes an acid-base reaction? A. single-replacement reaction B. decomposition C. double-replacement reaction D. synthesis

3.4 moles of solid CuSO4 is added to 1.8 L of water and allowed to dissolve. Will all the solid dissolve?

in the preparation of the unknown compound 1 g of powdered charcoal was used as a catalyst for the reaction. what is the purpose of a catalyst in a chemical reaction

A 1.2516 gram sample of a mixture of caco3 and na2so4 was analyzed by dissolving the sample and completely precipitating the ca as cac2o4. the cac2o4 was dissolved in sulfuric acid and the resulting h2c2o4 was titrated with a standard kmno4 solution.

My rib is sore and I have a bruise on my knee. What does that mean?

The force against a solid object moving through a gas or a liquid

Compare the evaporation of a contained liquid with that of an uncontained liquid.

What is the name of CH3CH2CH2COOH?

What do dipole-dipole forces do? A. Replace covalent bonds with hydrogen bonds B. Turn nonpolar molecules into solids C. Hold polar molecules together D. Hold nonpolar molecules together